How do I change defaults for ALL folders to open in List View

I'm running BigSur 11.2.1 and trying to figure out how to get ALL folders to always open in List View. This used to be possible, but that option seems to be broken now (all folders open in Icon, Column or Gallery, but not List).

If I use "View Options" to change to List view, the "Use as Defaults" button is greyed out.

I'm comfortable working at the unix level (terminal), so I've checked com.apple.finder.plist, and the default is set to "Nlst" (as recommended). I've wiped all ._DS_Store files, rebooted, verified com.apple.plist is still set correctly, but any Finder folders always are opening in Icon view.

Either I've discovered a bug, or I'm missing something so simple I can't see it.

How can I set the default for every finder window to open in List view?

TIA, Steve