To keep this brief I'm only going to talk about the big boys: Gran Turismo Sport, Forza Motorsport 7, Forza Horizon 4, Assetto Corsa, Project Cars 2 and Driveclub.
1. Gran Turismo Sport
The Good: It's a very pretty game. The Scenes mode is fun, and they kind of listen to fans. The car models are the best in the business.
The Bad: The economy isn't wonderful. I don't know why racing games have a hard on for making oval races the major money makers, but, GT Sport has one and I've done it a dozen times and...I'm never getting the 20,000,000 credit cars. Something that would help with this are prize cars, which aren't in the game, and the ability to sell duplicate cars for money...also not a thing you can do in GTS
The Ugly: It's an eSports title. Which means it's not very good. That's why the economy is crap, because it expects you to be a hardcore racing sim player and thus you're going to put in the 1000s of hours to get all the cars. And it also assumes you're an idiot because the first paid DLC has a money cap increase because paying real money to increase your fake money cap is...poetic, I guess. It being an eSports title I think is also why the track and car selection is a bit...lacking. It's slowly getting better over time, but PS5 and GT7 are getting closer and closer. And GT7 will be more casual gamer friendly.
2. Forza Motorsport 7
The Good: Massive selection of vehicles from the serious racer to the silly. But...that's why it's so good. I will admit that I've had more fun with FM7 than with GTS. But, FM7 isn't really an eSports game so, it's not crap...well...at least not for that reason.
The Bad: It's a game that's been out for 3 years and it still has some annoying bugs, like when you leave your single event race and then reenter it, there's a random chance that the game will completely ignore the settings you had saved and decided on completely different ones based on the car you were in. Also, when the game first launched, on PC, there was a bug that made it unplayable. See, what happened to me was, I clicked on "recommended settings" and apparently, Microsoft thought by "Recommended" it meant the settings the WANTED everyone to play on instead of the settings recommended for my 1050Ti because it switched everything to 4K settings. And I couldn't log in to fix those settings, so I eventually had to wait for an update for the game to fix it.
The Ugly: Three years out and it still is littered with bugs. Some of them are 3 years old. Turn 10 also was pretty all over the place with their updates. They started on drag racing updates and then moved to drifting and then to Porsche. The "Experimental Drag Racing" mode still isn't finished and they've moved on to Forza Motorsport 8...despite saying they weren't going to work on that until Forza 7 was fixed. Which it isn't really.
3. Assetto Corsa
The Good: Mod support on PC. A bit unexpected for a racing sim, but, it kind of saves the game, in my opinion.
The Bad: Because it's a "Hard Core Racing Sim" and also geared a bit more towards eSports, the game thinks anyone who plays with a controller is a complete and utter moron and if you play with a controller, the physics aren't wonderful. They're alright, but...Gran Turismo Sport feels better.
The Ugly: I don't know if it's true anymore, but I remember when AC first came out, the AI was the most rigid AI I have ever seen. Like, I had to slam into them at like 150mph to get them to move at all and then they magnetically filed back into their slot and continued on like nothing happened. Also, the amount of brake flutter the AI does is beyond ridiculous It really makes me laugh every time someone says AC is the best racing game ever.
4. Project Cars 2
The Good: Rallycross circuits with Any Car Any Track. Yeah, it's a blast to race the LMP cars around those tracks. Decent amount of tracks, too. Also, your tires don't explode in the rain like they did in the first game.
The Bad: The button lag in the calendar menu still exists from the first game.
Ugly: Shadows can be a little jerky in time progression A little too focused on the older race cars, if you ask me. Same with Assetto Corsa, really. I don't need 150 classic Lotus cars.
5. Forza Horizon 4
The Good: Great Expansions. Fun selection of cars. Great environment.
The Bad: I...don't understand why there are 10,000,000 credit cars in it. For a game that's supposed to be a casual open world racer, that doesn't seem casual at all. Especially considering the most expensive car in Forza 7 was the 6.5 million credit Bugatti Chiron.
The Ugly: But...that alludes to the major issue with Forza Horizon 4 and why I don't consider it to be the best racing game of this console generation. You see, Forza Horizon 4 just pretends to be casual, but...not-so-secretly, it's not. Sure, lots of not-racing game people have played and enjoyed it. That's good. But...nearly everything Playground and Turn10 have done outside of the Lego Expansion hasn't really been...casual-friendly. You'd think the Route Creator would be, but no. Once you've created a route, it can't really go back and edit them. You can at first, but once you've left the editor, you're SOL.
Then they added seasonal awards, where, every week, a new set of challenges is posted and doing those challenges can earn you exclusive cars. And if you're persistent and loyal and complete a certain number of evens per month, you can get more exclusive cars. And, there's nothing more anti-casual than locking away game changing exclusive items behind weekly and monthly events. Casual gamers, true casual gamers might miss a week or a month. And then they've missed that exclusive car. It'd be like if Call of Duty locked exclusive guns behind a series of weekly and monthly challenges. Everyone would throw a fit.
But, exclusive rewards were, apparently, just the tip of the iceberg. Now they've added a Battle Royale mode, the utter bane of all casual gamers. AND just to rub a little salt in the wound, they stuffed some exclusive cars in that, as well.
So, for a "casual" open world driving game, they're sure putting in a lot of work to reward the non-casual players. Which seems odd to me. And it's because of that I'd score NFS Heat over it, even despite Heat's Item Synchronization error. At least Heat wasn't heavily promoting it's online mode every time you turn around.
The Good: Good cars, good selection of tracks. Best weather physics in any game ever.
The Bad: Last game from Evolution Studios. And they're probably won't be a sequel. Also, the difficulty curve could be a little rough. But, then they added easy mode.
The Ugly: Having gone back and played it recently, I don't think the environments are that pretty, anymore and the vehicle physics can be a bit rough.
What's my pick for Best Racing Game of this console generation? Thinking about it....and it think it's a tie between Project Cars 2 and Driveclub...and maybe NFS Heat. If you want a good racing sim, PC2 is pretty good. It does have it's button lag, true, but, it's still pretty fun. If you want an arcade racer, I'd say NFS Heat, but wait for a bit. That Item Synchronization error is pretty brutal. Hopefully EA fixes it. And if you want something in between or just wanna sit in a car and watch the wipers realistically brush rain across the windows, then Driveclub.