Every single piece of my base (even the roof pieces) are supporting every other piece. 
My base has 4 ‘stilts’ holding it up- each is a scaffold touching the ground, surrounded by stem walls.

If I recycle any single piece (even the roof pieces at the every top), the whole base collapses. 

I’ve tried reloading a save, and restarting the game.

EDIT: I’ve just replaced one of my stem walls with a pine wall, and the whole thing is fixed. Although, now it says everything is supporting 0 pieces, which also isn’t correct. 
 

I'm having a similar problem. I can't recycle floor panels because it destroys the entire base. I started with grass flooring because of accessibility and now I can't replace them. So I am stuck with the grass flooring. Found this post because I am scouring the internet to see if there is a solution to this yet. At the time of typing this, my game is updating. Not sure what is included in that update. Hoping it includes a repair for this bug.