I understand the amazing graphics and driving experience... But I find driving games incredibly boring. The only recent ones that kept me interested were Forza Horizons with the open world aspect. Track racing is just a bit meh I find..
There is a huge difference between playing casual racing games like Forza or Gran Turismo on a joypad and playing sims like iRacing and AC on a wheel/pedal setup which can replicate the real-life forces a driver feels through a steering column. One is a casual experience lacking in immersion, the other is a very immersive experience that also uses up a lot of physical energy (the motors in today's wheel can put out upto 25nm of force, enough to break your arm or wrists if you're stupid)
These sims exist for people who love motorsport but can't afford to participate in real life, it's the closest thing you can get to real life and whilst it is expensive relative to normal gaming (hardware can cost thousands if you're willing to spend) it's still vastly cheaper than racing cars in real life.
If you don't enjoy motorsport then there is going to be no appeal to you, the same way that if you don't like football there is a strong chance you won't like FIFA.
That said I think if you got to experience sim racing properly and feel how immersive good FFB is you'd change your mind about it being incredibly boring... maybe not enough to want to do it yourself but enough to understand why thousands of people do it as a replacement to real-life motorsport.
On top of that the skills you learn in sim racing genuinely transfer over to real life hence why lots of drivers from numerous series (f1, indycar, WEC, GT3 etc) use them for training or for keeping sharp during the off-season.
TLDR: They are built for motorsport nerds not gamers