Simracing is one of the few things that can kind of quell my ADHD, and that's because of how many different systems are at play and how many mini-games you have to play.
First off, the driving. I was never a gearhead, but I loved the feeling of nailing a race track. Just hitting every mark to perfection. It's exactly what my AuDHD ass thrives off of. The fact that you have to be perfect to be good, and to be good you have to be perfect. That tickles my inner perfectionist.
Oh, and "the driving" doesn't just mean your braking, gassing, and steering. It also means understanding of physics and fluid dynamics. Every time you do anything you have to take into account that all the fluids in the car (gas, oil, coolant, water) will slosh around, changing the center of gravity. How does that affect the car?
And to top this point off, how does aerodynamics play in? Do you have a metric fuck ton (the actual scientific term) of downforce or are you just a brick with wheels? Is the air pushing you into the ground or just slapping your nose? How does all of this affect the TIRES? The TIRES, THE THINGS THAT ACTUALLY TOUCH THE TRACK. HOW DO THEY GET AFFECTED!!!!!!!
Then there's the strategy. In most races you have to pit, either to refuel or change tires, or both. You have to plan, even if it gets torn up at Turn 1 and you have to think on the fly. You are ALWAYS busy when racing. There is no downtime. You have a stream of information entering your data receptors at every given microsecond, and you have to process it at such insane speeds that you're at risk of putting a calculator out of a job at times.
OH BOY and then there's the fact that if you wreck, YOU MIGHT NEED TO KEEP GOING. WITH A DAMAGED CAR. THAT PERFORMS DIFFERENTLY. AND CHANGES EVERYTHING YOU KNOW ABOUT IT. It is the DEFINTION of Adaptation.
And speaking of Adaptation, there's the weather. Weather means everything in racing, and that transfers to simracing too. Too hot or Too cold and those tires I mentioned before won't grip right. Too hot and you'll just burn up the rubber, literally melting it at times. Too cold and you'll just be running on hockey pucks that don't do a lot of grabbing at the track. Is it wet? Are you running treaded tires or full on slicks? Is there rubber laid down on the track from all the other cars over the race? Once that rubber gets flung off a tire it has to go somewhere, and usually that's the tarmac. It sticks inside all the nooks and crannies and makes a slick surface, one that tires grip better than raw tarmac because it has a wider useable surface area, but in the rain that means the water has nowhere to go, so no matter if you're running treads or slicks, it will be much easier to aquaplane! So you now have to run a DIFFERENT LINE or JUST DEAL WITH IT AND GO! ADAPTATION!!!!!!!
Add all of these little things together and it's an experience that's almost perfect for someone with my particular variant of AuDHD because I have all these variables to pay attention to with one big goal in mind that I NEED TO BE PERFECT AT TO GET. I didn't even mention how as fuel burns off the car gets lighter, how downforce actually affects braking distance, how draft and dirty air are the same thing but one is beneficial and one is harmful. That's how insane SimRacing is, and I only operate off of 2 senses!!!!!! The real guys use every sense in the body!!!!!!! I'm not even getting the most out of this hobby but I'm still able to just calm my mind by turning it to 11, and it's RELAXING TO DO SO!!!!!