As far as I understand, yes. There is conflicting documentation out there, and I'm not an engineer so take this with a grain of salt.

That being said, in order to write new data to a block it first has to be zeroed and then written. The idea behind trim and GC is for the block to already be zeroed before you'd want to write to it, therefore improving the perceived response of the drive. There are of course other purposes behind the operation, but it makes sense that if you need to zero an entire block BEFORE you can write to it, you'd want to zero it preemptively and not immediately before a write.

Higher in this comment chain is an article from crucial who describes trim & GC working exactly in this way if you'd like some reading on the subject.