Why is my iMac not saving files to the desktop?

Same issue as others have hadwhen freeing up space on my iMac. Nothing saves to the desktop; only my hard drive and externals are showing there. If I go in my Finder, I have a secondary desktop that has stuff I need. WILD. Have tried the fixes here I can perform easily aside from TimeMachine (I have work projects I don't know for sure have gotten backed up appropriately), no luck.

Come on, Apple techs. Figure this out. We shouldn't have to fix this ourselves. We're spending way too much money on the front end--we need devices that just WORK.

[Re-Titled by Moderator]