Also generating subtitles for my mother’s foreign films I guess?

You mean mapping learned patterns (speech) to other patterns (words)? Yes, that’s actually what it’s really good at.

Of course, if those films invented completely new words, it would be out of its depth. Weird pronunciations may also produce weird text. It might get things wrong either way occasionally.

But if it’s within the boundaries of its training material, it’ll generally produce reasonable output, and in that context, the occasional aberration doesn’t matter as much (particularly if the human brain can compensate).

Just don’t ask it to generate anything where factuality matters.