It's fun i played 3/4/5 on pc but always went back to the crew after a few weeks i enjoyed it more but couldn't say why exactly.
I've thought quite a bit about why I find TCM so much more enjoyable to play than FH5:
1. The hugely more varied events. You've got races with tyre wear and pit stops, races with instant nos refill, races with time bonuses for clean driving etc. Tracks can also differ a lot in style, ranging from some barriered pure race tracks to "follow the clues" tracks with huge cuts to work out.
2. The competitive element of summits. FH5 has zero challenge, so it's just a chore. Even though it's really too easy for me to get platinum in TCM summits, the fact that there is a leaderboard for every event and for the overall position means I can challenge myself to do better, e.g. see how close I can get to the times done by content creators (and even beat their times on some occasions).
3. Grand Races aren't bad at all, and IMO better than multiplayer in FH5, and also better than the ranked racing in FH4. I think there is scope for them adding ranked racing for the "no collision" grand races, but ranked would be a disaster for the grand races with collisions on. The collision grand races are pretty bad for ramming, but no worse than FH4/5's multiplayer, and the longer races mean that you generally get clear of the worst of the ramming. The slipstream effect is a bit annoying, as it means people doing the races in a group have a huge advantage by staying together as they can always catch the leader if they've been gapped, or gap a solo player behind them. I have around a 20% win rate in grand races, but have seen some other people in them who have a very high win rate, and those players are genuinely better than me, so statistically, over many grand races, better players consistently finish higher up, on average, than worse players. Also, because there is just the one multiplayer option, grand races, you can queue pretty much any time of day and very quickly be in a full, or close to full, 28 player lobby.
4. The progression system with the parts and legend points is IMO a very good "carpg" element, massively better than what they did in FM for their "carpg" attempt. I have the game now on 4 accounts because I find the progression so enjoyable. I've specifically not done any grinding for parts on the alt accounts, instead just enjoying the satisfaction of gradually getting first half sets of gold parts, then eventually for the really commonly used categories, occasional full sets. The parts aren't needed for grand races, so a new player can very quickly do grand races with a level playing field, and I think this is a great choice by IVT. A new account can very quickly get platinum in summits using pink parts, as the ability to merge 3 blue parts into a pink part makes it very easy to get a set of pink parts.
5. The absence of significant building/tuning. It takes hours and hours and hours to mess about with just one car in FH/FM and I hate it. You can try other people's tunes but they never match your driving style, and you can't tweak their tunes, you have to start from scratch. I hugely prefer TCM where you can just take a car, do some standard things to it (widen the wheelbase if available, put the best tyres on, stiffen ARBs, reduce cambers, set front/rear power and brake balance). And if you do want to adjust the tune more, people share tunes on YouTube, so you can try their tune and tweak it if you don't like it.
6. It took me quite a bit of time to work out the best controller settings and assist settings, but having got there over several months I find the physics and controller handling in TCM absolutely fantastic. FH5 feels like garbage to me now by comparison, it's just so sluggish. The fact you can separately adjust controller sensitivity for steering and counter-steering is frankly revelatory compared to any other game, as far as I'm aware. It absolutely blows away even AC EVO in this regard, which doesn't separate the two so you end up with the car oscillating one way then the other in a way it would never do in real life.
7. The strategic element provided by the NOS. For example in grand races, the interaction between this and slipstream takes a lot of skill, as you can try to gap people by using more NOS than would otherwise be sensible, to drop them out of your slipstream, and you can also use an unsustainable amount of NOS to try to avoid being gapped, using the slipstream to let it build back up. It's a strategic element in the races that is absent in FH/M.
8. I like the much greater range of visual customisation in TCM vs FH5, and I also like that the visual customisation mostly doesn't affect performance, so you can just give your cars the appearance you like the most.