If the turbo is functioning properly and is not damaged in any way, the only thing controlling boost is the wastegate. So, if you pinch the wastegate hose, in theory, the wastegate cannot open.

However, if the wastegate valve itself is not seated for any reason, then it allows bypass of exhaust gas and may limit boost. This is a rare occurance, AFAIK.

If you pinch the wastegate hose and get boost that climbs over 11 psi, then you know the wastegate spring needs adjustment.

Be careful when you drive it with a pinched wastegate hose. Watch the boost carefully. It will climb pretty quick if things are working properly.