I'll quote my favourite author, Erich Fromm:
"The liberation from the machine has resulted in the ideal of absolute laziness, of the horror of making any real effort. The good life is the effortless life"
why would you want to waste your time when you're done with your duties (studies, work or whatever)? Use it to improve rather.
The only usage for Netflix that I see as being productive is if you learn a language with it.
(OK ofc it's ok and necessary also to be lazy sometimes, but Netflix is addictive, I tried it and then would spend a whole day chain watching braindead series for example, which is super bad)