I was the one who quoted that the turbo cars pull harder with thinner air.

Elevation in feet: 3333
BHP at Sea Level: 215
Brake Horsepower Loss: 214.9785

The turbo is setup to provide boost up to wastegate pressures. BUT the amount of boost is determined by the speed of the impellor ( driven by exhaust gas speed ) and the wastegate control.
So turbos take longer to get the boost going and don't initially increase power at the same rate as at ground level. ONCE the turbo is spinning fast enough and producing enough boost for the wastegate to want to bleed some off THEN it is at the same power as sea level. So at higher alts they tend to be more laggy and more peaky.
BUT with MODERN ECUs this often re-maps and shifts the wastegate actuator electornically as opposed to earluer/cheaper mechanical

on n/a modern ECUs can alleviate the problem of altitidude reduction in O2 but not remove it completely. So todays cars are a LOT better than older gen