I have been using the gestures for months also. I see zero benefit, literally zero. The gestures are fine and I am used to them. But they provide absolutely no benefit to my daily use. I picked up my wife's phone and it was a relief to have a multi-task button again. Sliding some of the way up, but not all the way up is no benefit compared to tapping a button IMO. Sometimes I go too far, or if not I have to gl slower so I don't go too far and get the all apps screen, etc. It's fine really, but still..
Sometimes people complain for all new stuff, sometimes though the new "features" offer no improvement or regression, and we end up with change-for-the-sake-of-change things. In which case, it may need to be called out.
Bottom line for me is choice. If Google allows us to choose one or the other, great. If not and they force this on us, then not so great.