I don't think you understood the point. It's not that there are no alternatives to simulators. It's that there are almost no hardcore simulators today that aren't dry, serious, circuit-based motorsports simulators.
Like you, I want PCARS3 to be the best sim it can be. But I enjoy driving/doing different things than what you probably like to drive or do! It's about that simple.
That is part of the purpose of roadcars, fictional/city locations, and upgrades. They're not only for casual/novice racing game fans. Roadcars and upgrades are part of automotive enthusiast culture. So is illegal street racing, and fictional/city locations are a common way to offer something reminiscent of street racing while avoiding upsetting any lawyers, to be enjoyed in the victimless context of a videogame.
(Really, fictionalized/virtual illegal street racing is a distinct subculture from illegal street racing itself; a celebration of cars.)
Sadly, getting that kind of content in an accomplished realistic simulator is rare. About all you can typically find are scraps in circuit-based sims like this one. So maybe you can imagine my frustration whenever there's so much friction against the idea of offering any scraps at all.
"That's not what a sim is," you might be saying. "Sim" is a description of the design approach of a game, not whether it restricts its scope to ordinary authentic motorsports and the associated expectations. A sim is simply a game that simulates something, whether it's GT3 cars, roadcars, logging trucks, banger-racing cars, planes, trains, or city planning.
There is literally no other way to realistically simulate drifting a modified roadcar down a mountain pass...but in a sim.
You simulate it the same way you simulate the car in the first place: by feeding the revised torque curve into the engine model and the new stiffness/damping/etc. into the suspension model. That is something racing teams do with their competition-grade simulators, to experiment with suspension changes and so on.