Due to space limitations, no. I sell everything that has no current value in the game except for selling it.
Think back over the history of the game, since 2014, and try to count up all the times they gave purpose to a previously useless and incumbent asset. I get to zero. I don't think Fd does placeholder assets.
Now, count all the times they added new content and with it spawned a hundred totally new assets for it, isolated from everything else before it.
This is the logic I follow when I decide to not hoard stuff that takes up space. We're not going to be using those AX Defence Protocols any time soon. And building schematics?