Just for the record... to add this to our AC AI F1 conversations... I just had a marathon week where I played F1 2020, F1 2021, F1 2024 and finally tested F1 2025 on my brother's PS5. I have played F1 2023 before but I don't have any clear memories of it despite throwing it away from my hard drive after 2 hours of testing. I recall it had some real issues with AI. 2021 felt decent too... but the rest... forget it.
That said, I have no knowledge on career modes, buld a team features etc. on these different years because I'm not interested in that fantasy stuff at all.
Easily the best game of the series is F1 2020, it's not even close. It's actually very good game that portrays modern F1 quite well.
AI observations from F1 2020 (best of the bunch).
I used HARD 70 level on F1 2020 which was plenty challenging (for me at least). AI is overly aggressive in all overtake situations. I mean top drivers (in this case Verstappen and Hamilton) are not giving you space fairly even when you have the better line but rather crash you on the tight corners. I mean it doesn't happen occasionally but pretty much always. The issue is worst on tracks like Baku and Singapore.
I have fixed that issue on AC by keeping the max. aggression at 25 (you remember the video I posted a few weeks back). I'll give AC ai an edge here. Overtaking now is much safer and more realistic on AC (at least when you don't have the DRS edge).
DRS/ERS are very well implemented to the F12020. Mandatory pitstops work great (I had to use automatic otherwise I lost too much time compared to AI which pits perfectly). I haven't played a lot of modern F1 mods and I don't know how well these are done on AC (as it's depending on the tracks and cars). I would think F1 easily gets the edge here. You can also make the DRS/ERS automatic which I used because I hate pressing buttons all the time.
Blue flag/outlap AI is excellent. AC doesn't even have this AI which is its worst sin
Even FFB is "semi decent". There is not much feel but at least it's consistent and precise after you maximize the FFB saturation. FFB is not even from the same planet as on AC or iRacing. Or even ACC or RBR (which actually has excellent FFB). But the physics and handling feel much better than on any of the other Codemasters games.
Interesting that Lando Norris commented these games that driving the actual F1 car is much easier than driving the Codemasters games. He said that there is way too little grip when you play without TC. He also stated that when you use TC it feels much closer to the real thing.
That's interesting as most F1 mods on AC have WAY LESS grip than any of the Codemasters games... not to mention that AMS2 classic F1 cars are oversteery like E30 BMW's. However when you use full TC on F1 2020 it's definitely overboard.
I have some karting background but of course I haven't driven a real F1 car (that goes without saying hehe) but I feel there's a general misunderstanding that more difficult automatically makes the sim / car more realistic. I don't think that is the case. Coach Dave (a real GT3 driver) said the same thing to LMU and iRacing developers when he was testing their sims. He said that there is not enough grip in your games... and the cars are way too wobbly and the kerbs are way too unforgiving (this is the same sin on almost all sims)..
I think Kunos F2004 is too oversteery and the very well driving modern F1's on AC are VRC 2005, 2007, CIM 2008 (yeah I know 2008 cars didn't have TC but it feels great with TC) and the RSS Formula Hybrid 2022 (it's the only really modern F1 car that I have bothered to try). I think many sim racers WANT cars that are more difficult to drive which I understand in a way... but something like Kunos RUF Yellowbird is just laughable presentation. THAT is not realistic at all... it feels like driving on oil or ice.
Another thing where F1 2020 edges AC (besides the accurate rules of course) is the amount of AI difficulty that you are able to increase. I feel that AC at AI 100 can be too easy sometimes and you have to "hack" your own cars' aero CD GAIN to give yourself slower car, etc. That of course depends greatly on the cars.
Summary: Nothing still beats AC on ANY classic F1. Codemasters F12020 can't quite compete in the driving/FFB department but it does everything else so well. You have to wonder why their game took a downturn from 2020. Maybe because 2020 was the last one developed purely by Codemasters?
I also tried F1 2010 and there's not much to tell hehe. But F1 2020 is surprisingly good game. It's not available on Steam anymore but I can give it to you on PM if you want to try.
This also raises the question: "What is a real sim"?
F1 2020 has superb blue flag AI, perfect rules, decent AI (a bit too over aggressive though but they don't do any stupid things on the track like stay crawling there after getting damage, like on AC), very good graphics, plenty of setup adjustments and I have a mod that changes all correct ad banners to every track, perfectly implemented DRS/ERS and decent damage model. Although F1 2020 steering is "numb" it's still accurate, sharp and very usable.
The only department where it clearly loses to "real sims" is the force feedback. We don't know about the physics because none of us have actually driven a F1 car. Does the lackluster FFB alone make it a "simcade" although it beats "real sims" in almost all other departments? Sure it's a one purpose dedicated F1 game and AC is just a general sim... but still... hmm...
I don't recommend buying any of the new F1 games. I didn't play them excessively but something in the driving is clearly off and they cost... what... 80-100 euros. That's insanity!!!!.
PS: I also installed GP4 and some mods after some 10+ years break from this game. Time has not been so good to GP4. Nostalgia is great and it still has some unbeatable details (like damage model and good AI) and some AMAZING mods done by the community but it still felt a bit like going to your grandpa's closet and borrowing his 70's jacket.

I must re-check RF1 now... it's been YEARS since I played it hehe.