The problem for me is when an icon is repeated many times on a page, such as once per row. The word quickly becomes redundant, and the repetition looks ugly. Tables are supposed to be information-dense and wasting screen real estate interferes with the user's task.

I haven't found a good general solution to that. Hover doesn't work on mobile. A legend map is hard to locate. "Expert mode" introduces new problems.

Sometimes I'll just use an unlabeled button and make whatever it is undoable, so that users can just click and discover. But that's hostile to completely new users.