Waterfall refers more to the fact that further work (development, testing, or deployment) has to wait for someone else to finish something else first. Multiply that by how many “steps” something has to go through before being released. This implies everyone is taking work in large chunks instead of small iterations, and that too much is being planned too early instead of learning as you go.

Taking things iteratively, small iterations, delaying decisions, learning as you go — that’s what agile development is. And all the stuff you mention above is possible when developing with agility.