Linear, linear, linear

[Atelier-Bagur]

I guess I'd view that as a problem with "later content" not actually doing anything interesting or doing anything outside of a tiny, formulaic box.

Why is it a problem that content piece X has a mechanic that's seen no where else?

There's nothing wrong with it. Its just the mistake of having those mechanics be present as the "tutorial" bosses. If they've applied those designs to a later boss (which arguably would probably fair better) down the road then it'll be great.