You seem to get bored of cars at an insane pace (and I thought I had car ADHD
). Based on that I would recommend you pick up a used G29/T150 wheel, used Playseat and a used PS4, then grab a copy of F1 2020. If after a few months you're still passionate about it then you can upgrade.
IMHO a Thurstmaster T300 wheel & T3PA pedals are the best of the "cheap" setups, if you've got the room grab a proper cockpit as the flex of a Playseat can get old fast, as for TV's get a 4K with 120Hz.
Making the jump up to PC & iRacing is a big step up, you'll need a fairly powerful PC and either a triple monitor, ultra-wide monitor or some VR goggles, either way it adds at least $2500 to your sim build costs. If you just want to play F1 or NFS then I think it's safe to say a PS4/5 and TV is more for you. The jump to a PC and iRacing is more than just the extra cost, it's far more involved and time consuming. And when it comes to PC/iRacing the sky is the limit, places like the Race Room have sims that are well into the 5 figures if you want to see what a high-end full motion rig can be like.
I've got a pretty good rig as far is PS4 rigs go and the only reason I haven't made the jump to PC & iRacing yet is there's a good group of guys (a couple beyond members too) who I race with weekly.