Sure, DV should come with care no disagreement there.
Misplaced/misused tags would be a great example of how to use a downvote.
Someone might get a DV one day, and many UV the next with no DV or a bit of both. I don't think it will discourage anyone ( or, shouldn't). They just need to learn how the Steem blockchain as a tool is used as w/ anything new.
To borrow a line from Spider-Man's Uncle Ben "With great power, comes great responsibility."
If people are genuine, they will generally be receptive to communication regarding anything that is frowned upon. If that communication falls on deaf ears or is essentially ignored, then those individuals are probably not that interested in being part of the community anyway