I use year based tags for some of my annual planning. (ie something like: #2021.Q1 #2021.Q2 and #2021.01-January etc.)
I don’t want to delete these tags because they are helpful when I look back at past years, etc. However, I also don’t want them popping up in the “Tag Auto Complete” search anymore either. If we get some “tag management” features, I would appreciate an option to “archive” or choose to have some tags not show up in the auto complete popup.