Yes, like speaking will not make you better at comprehension, although comprehension is required to have any meaningful conversation. Speaking needs to be practiced, but input and understanding comes first.
I'm pretty sure the originally poster did not mean to never speak at all. But just not to worry about it for a while.
I don’t see any reason to delay practicing simple phrases like “Hello”, “How are you?”, etc., or practicing the pronunciation of the vocab that you’re learning. It takes years to be able to reliably comprehend naturalistic conversation. You can’t realistically delay speaking until that point.
You definitely can, but whether it's necessary to delay simple things like that, I'm not sure.
It's pretty simple to speak things that you've acquired (of course it'll be slow and awkward at first, but that's natural), I just don't think there's much point in trying to speak things you haven't already acquired.
