That would imply taking a positive action to do something about the tab. I want to just ignore the tab until I need it again. I don't want to treat the tab specially.

My real desk is messy. I mostly know where stuff is buried because I put it there and nobody messes with my desk. I clean it about once a year, usually when a big project is fully done forever. I want the same functionality from my browser.

Yes. What I do now is save the page as an mhtml file so I can read it later without having to find it again. (Chrome should really offer better mhtml support.)

not going to touch an extension

Extensions tend to break with browser updates. Extensions tend to cause slowness. Nobody wants your bug report if you are running an extension.