I think bumping threads is over-chastised, and you will rarely see me complain about it. I believe bumping threads is a very good thing to do if there is additional valid information being added. This is the advantage of a Forum over other communication methods (reddit, discord, etc) - information from the distant past can suddenly become relevant again, and the history of the past is immediately available. We as moderators should be very judicious about complaining about bumped threads.
If someone bumps a thread to say something silly like "I agree", that's not a good bump, and it's valid to criticize it. But if someone is adding worthwhile information, we should never chastise those bumps - being able to do bumps like that is one of the very nicest features of a Forum.
If a moderator criticizes a bump, it should always be done with a justification showing that there was no real information added by bumping it, and that it is not a topic that has suddenly become relevant again due to some important related event.