That's grossly simplifying the whole discussion to somehow make your point more appealing, but it doesn't really work in this case.
What does that even mean?
I have no idea how you can possibly argue against upscaled pixels becoming blocks, really.
You asked if "blocky" can even be used to describe pixel art. It kinda does describe what pixel art is all about, doesn't it.
Placing blocks. Pushing pixels. Using a low resolution and zooming in.
Zooming in.
Zoom into something and you'll eventually see blocks.
Maybe you look at tone over content when calling me arrogant for saying there's no room to argue against that but where exactly are your arguments against this again?
You have not yet provided anything of substance to give your point a foundation apart from "I don't like this word".
I don't see how your point has any more validity then mine, then again, you use the term "appealing" which probably means you don't look at this objectively anyway.
Calling an upscaled low-res game "blocky" doesn't even have the same negative vibe as calling loud metal music "noisy".
Maybe it's a clumsy formulation but it's not entirely wrong.