Saying nothing at all is better than only being allowed to say good things and none of the bad. The former doesnt shift opinions in either direction but the latter introduces a pro-buying bias to reviews. Good for the publisher and no one else.

It's worse.

Playtest results inhibit you from disclosing things because they are subject to change. They take gamers'feedback, decide if they want to act on it, and at the end of the day the finished product may look different so it makes no sense for people to loudly state "they have feature X, and they don't have feature Y" because by release it may be the other way around.

Whereas this type of contract says "idgaf what's bad about the game, you can only sing its praises online".

Silence > dishonesty.

If it's actually a closed beta then it shouldn't be open to streamers at all. If are going to allow stream is to play it then it's not really a closed beta. It's a marketing gimmick.

I think the difference is that those play tests we are thinking of are for lack of other terms locked down. Playtests I have done were not able to be recorded, streamed and had water markers all over the place. In this case people are playing and streaming making videos at that point you should be able to give opinions on the game.