US elections are at least superficially free and fair. Imho leaders that don’t hold fair elections also give up the expectation of other nations keeping out of them.

So while there is certainly back-and-forth here, I can’t see any moral issues with anyone meddling in Russian elections. It’s likely even necessary if the current regime is to be changed (which I think will be harder than in 1990).

The US obviously also meddle with more or less acceptable means in countries that do have free and fair elections but that’s a different topic.