There are studies explaining the appeal of the "chore simulators". You should look them up because I may not do them justice, but in a nutshell it's basically that they are very satisfactory because they present clear rules, they allow you to "do a job" and if you do it well, you progress. There are no tricks, no unexpected crisis, you do the thing, you get money, you get better gear, you do the thing better. This is escapism for people frustrated with "real life". Real life sucks. Sometimes you work hard and you still don't get "better gear".

Driving simulations - be it planes, cars, trucks, boats, etc - are maybe a bit different, but essentially it's just a combination of chill vibe, romanticized experience (the classic "I wish I could be a farmer", no you don't) and a degree of what I described above. Obviously there are also people who are just passionate about trains, planes and such.

The chill cozy games are a real trend, and it's due to what I described in the 1st paragraph.