Posts have bad tags or poor topic suggestions

Try posting and you'll see what I mean.   At the bottom it says "Topics help users find your post.   Please select one or more topics."

The ones offered are very general.    If I wanted to help users find my post about blend modes, I see no tag down there that I could click that says "blend modes" or "blending" or "multiply" or "overlay".    Instead, I can choose "macOS" which applies to everyone with a Mac.