I'm not sure exactly what you are asking. Is one form of M1 better than another for turbocharger life? The answer really is no, any M1 will tolerate turbocharger bearing heat without coking. If you are asking whether 0W-20 is a good choice for turbocharged engines, that's another debate entirely.
I'd answer the question of low viscosity in a highly stressed engine with this. We hope manufacturers alter the engine design in every aspect necessary to ensure long life. AND manage oil temps to ensure safety. Even mighty Toyota is experiencing rampant bearing failures in their turbocharged truck engines. Seems to be a combination of low oil pressure and low viscosity. No magic bearing design is going to fix oil starvation.
Oil starvation can happen when conditions are right. One towing test of a new turbocharged engine had the engine shutting down due to high oil temp and loss of pressure. Maybe the software saved the engine, maybe not...
In the case of my supercharged Jaguar F-Type,,, Jag increased the size of the rod bearings and altered the timing chain design to tolerate 0W-20 oil in all conditions. Fantastic. Except the main bearings were not increased in size, and the cam lobes+DLC coated shims last only so long with the 0W-20. My point, Jag did not address every potential issue and users pay the price. I use 5W-30.