Why do Finder tabs and toolbar disappear?

I work in the Finder with a single full screen window with multiple tabs with the header hidden. I don't think I'm the only user who works like this. Here you can see the top of the Finder window with toolbar and a string of open tabs.

Every tab has a little checkbox to close it, as in Safari. If I click it this is what I get.

No toolbar, no tabs. This drives me absolutely bat **** crazy. Not because it's still happening in Big Sur, which is probably at the end of its development, but that this incredibly stupid behavior has been happening for years, literally years, through multiple OSs and into the next, ever since tabbed Finder windows were introduced. Why can't this be fixed? If it can't, let's just drop tabbed Finder windows so we can get past this embarrassing farce.

I'm appealing here in the distant hope that there is a trick or setting somewhere that can make this work in some semblance of sane software behavior.

Thanks very much.