Uhh about that. Sure it would sell but probably not the amount of a 911. Which sells around 9k-10k units per year on average. It seems like whenever someone compares sports cars today, it's always compared to the porsche cayman or 911, or the Chevy corvette.
Dude are you high? The people considering a new base 911, a C8, and a hypothetical done-right 70-90k Supra turbo are all wildly different buyers.
Have you ever talked to the owner of a C8, or a brand new base 911?
The three cars you suggest attract three VERY different buying demographics with very little cross-shopping.
The majority of 911 buyers woke up knowing they wanted a new 911. An enthusiast would be looking at a 911 turbo that's a few years old vs a new 911 base model. 911 base models are for trophy wives and cork-sniffing boomer tourists who decided they wanted a sports car, know nothing about sports cars, but are too cunty to be seen in a domestic or Japanese offering and a BMW, Audi, or Mercedes all look the same to them. So base 911 it is.
The majority of C8 buyers woke up knowing they wanted a C8. The majority of them are domestic-car fans and are overwhelmingly retired boomers doing the midlife boomer Corvette thing.
Those are very specific buyers and fairly myopic in their tastes/preferences with very little if any cross shopping between brands.
A hypothetical 70-90k Supra turbo done right would get compared to those cars by all the
clickbait generators (ahem) car bloggers and yoot00bers because that's their business model is generating crap people will click - relevance, insight, or accuracy is not required.
But most of the buyers for the MKV Supra aren't cross shopping new base 911's or C8's. That is not just about price, most MKV buyers by their stated demographics are overwhelmingly capable of buying a more expensive car if they wanted to.
Plus there's countless dudes like me that are sitting around still spending that money on 90's shitboxes, because despite being in our peak earning years and absolutely having the income to buy a 70-90k new car even with current interest rates, there's literally nothing new on the market that's gives any of us 'the fizz' as James May so eloquently puts it.
Toyota flubbed it bad. If you're buying the shit they're shoveling they go ahead and buy it, but please stop shoveling it here - we're not buying.