A few Cossies have been done in the past.

The main reason it seems nobody does em is people dont understand em much in the UK, so all we ever see is high compression low boost jobs pushing out fairly low power, 150bhp per litre type things at best.

Overall a turbo is way better, but the instant response of a s/c can be a big big advantage.

Ive been in a 400bhp 2litre supercharged 306, and it was mega impressive, worked way way better than a 400bhp turbo on a FWD car, but that was as it had a centrifugal supercharger, so didnt have as much midrange as a turbo or positive displacment supercharger, meaning loads more traction.