By your logic, no one should ever translate anything! They may be here to read the ANN, not take part in discussions, dev talk
The translations I have seen here so far haven't even been good ones. But announcements for coins, tokens, services etc. don't really bother me as long as they're confined to their own board or sub-board. But flooding local sub-boards with ANN spam would easily drown out other discussion.
And yes, of course it's possible that users are actually flocking here to read advertisements rather than to discuss other matters. But I'm speaking for myself, not for them.