It’s possible to deliver criticism in an optimistic way, if it’s impersonal and concrete (according to M Seligman). BTW, that’s also a standard for academic criticism. But there is a difference between allowing only optimistic criticism and banning criticism at all. That’s the problem with both tech culture and academia these days.
The hope is that it creates a can-do culture. Downside is that it can create a culture where no one feels safe criticizing bad ideas.