[suls]

Not trying to defend them but I often see these sentences when Japanese is translated too verbatim. 「申し訳ございませんが…出来ません。」is a very formal way of saying this. Context then of course tells the receiver if they really can’t or just don’t want to ..

[grapeskin]

Even in Japanese it has the same context.

When a company simply chooses not to do something, they often use 致しません。When they use 出来ません it would mean not possible (eg unable to ship an order due to time constraints) or because they want to pretend it’s too difficult and unreasonable of a request.

[gimmeThaBeet]

I don't know much Japanese, but yeah that's one of the ideas that comes up immediately. Definitely not my place to say if it's too verbatim, the one I've heard several times is muzukashii / 難しい. I think it's hard to translate because just 'no' loses part of it, "no thank you (but I didn't actually say no)". So it sort of develops into the translation having a coded meaning, where difficult things are 'polite' refusals.

[posterboy]

They are patently unable to