Hidden interface controls that affect usability

Not sure I agree with all of the OP's opinions. I prefer a clean, calm, uncluttered user interface over a noisy, busy, cluttered one. In the OP's example with maps, I'd rather see a full-screen map, instead of a map that is always partially covered by a bunch of big buttons, obfuscating my view. Please let me see the map. Yes, fill the entire screen with it.

Gradually, over decades, society has evolved a "shared language of touch-screen actions" for controlling touch-screen devices. Many actions are familiar to everyone here: tap to hide/show controls, press and hold to bring contextual menus, pinch with two fingers to zoom out, etc.

It's OK for UI designers to assume familiarity with this common language to keep UIs clean, calm, and uncluttered. I like it.

The real problem is that there is no one sized fits all paradigm to rule them all. People will want different things. Watered down UIs that cater to average will never please those with more niche preferences. It's hard to get right but offering multiple competing options which cater to different segments is the only solution that seems to work in my opinion