Not as far as I can tell, where intended is ‘as any user would reasonably expect’. Bricking the drive (can’t even read) because of too many errors is not what most users would ever want.

Some would (enterprise maybe), but even then they’d want deterministic data deletes too, which doesn’t sound like are happening.

You can argue that controllers shouldn't behave that way. But they do, it's not a bug, and it's not a dead controller. It's a perfectly functional controller's response to dead blocks.

Cite? By definition it appears to not meet the definition of ‘functional’.

The definition of functional in the context of the discussion is that in works in the way the manufacture explicitly designed it work, in a standard industry practice fashion, not as an unforeseen bug or malfunction.

Not some abstract notion.

So not enumerating as a drive, and not allowing you to read even valid blocks is ‘working’?

Yes, same as a facility self-destructing, if it was programmed to do so, is working as per its spec.

And what spec requires that? I have yet to see one.

The manufacturers'.

Cite? I have yet to see that actually documented anywhere, and you keep avoiding actually referring to one either.