Best offline experience ever -- but there is a problem

As in the title, I just had what I think was my best SP experience in a sim.

One hour race at Spa, 48 cars, tyre wear and fuel consumption at 2x. 2 pitstops forecasted. AI at 115% strength, max aggressiveness.

Bad qualy, started twenty-something-th. Climbing up the field and noticing, by the live timing at the left (which is terribly bugged ATM, BTW, gaps shown are useless half of the time), that there was plenty of action ahead, quite a few lead changes. P11 at the time of the first stop.

Magical moment #1: in the first pitstop, about half of the grid doubled their tyres. The field spreads.

Next laps were amazing, quite a fight. The guy I thought was gonna win showed up in front of me in P8. Watching the replay I learned that he had contact defending his position at Campus, and lost some ground.

The second pitstop apparently got strategies even, I believe everyone had 2 pitstops but did tyres only once by the end of the race.

Magical moment #2: Before opening the last lap, the guys ahead touched at Blanchimont, one of them spun and I had to avoid the uncontrolled car going backwards while facing the wrong way and crossing the track.

P9 at end I think, it doesn't really matter, it was a fantastic experience, better than most of my recent attempts online.

There is only one problem: the cars were Renault Clios from a Clio Cup mod.

I never got such a race from original content. The variation of strategies (they never seem to double tyres, even in a track like Le Mans), the realism of the incidents, etc.

I wonder why, and I wish it weren't the case.