How do I restore the "Use as Defaults" button?

Greetings,

In an effort to change the default view options for all my Finder windows, including windows I had previously changed, I ran the following command in Terminal:

sudo find / -name ".DS_Store" -exec rm {} \;

Apparently, that broke something, because now the "Use as Defaults" button in the view options window is grayed out, regardless of which directory I'm in or which view options I select. I'm absolutely stumped.

Running OS 10.13.3. Any ideas on how to fix this? Thanks in advance for your help!