Note that ớt is hot pepper, chili pepper, not black pepper. Black pepper is tiêu.
Of course the stuff you eat with fruit, which doesn't really have a natural english pairing because it is not a common english combination
why would salt and pepper not be accepted here? That is how we would say in english
Because ớt means chilli (peppers) not (ground) pepper which is tiêu. Muối ớt is chilli salt which is quite popular in Vietnam.
salt and chili would probably be a better pairing in english and saying salt and pepper will cause people to associate it with black pepper (which isn't yet covered(?))
It's quite simple really; in the case of salt & pepper you have two condiments thrown together but they're still both separate while in the case of chilli salt, the salt crystals themselves are infused with the other respective ingredients. This is also why we say chicken salt because the flavour is imbued into the salt itself. Salt & chilli would bring to mind something entirely different: salt with cut/sliced chillis. In this case if you wanted to say salt & chilli you'd say something like muối và ớt (xắt).
Then the translation should really not be peppers and salt doubly for the reason A: it confuses black pepper with chili and B: it suggests chillies mixed with salt rather than the amalgam it is in fact referring to.
I agree that "salt and chili" may be misinterpreted as salted chili peppers, but "peppers and salt" has the same problem, and it's more vague. It could be misinterpreted as salted chili peppers, salted bell peppers, etc.
There's no perfect translation, but I'd say "chili salt" is closest. It's not commonly said, but I think it's pretty unambiguous.
Chilli salt is a thing separate from chilli (peppers) and salt. Just google images it! Luckily as an Australian we don't get chillis and pepper mixed up so salt & chilli vs chilli salt are both distinct.
I understand chili salt -- the meaning is clear even though it's not common in English countries. That's why I'm suggesting that chili salt should be the preferred translation.