Comment 6 for bug 1960885

Tested on MOBIUS Test Server 2. Does seem to now work as intended.

Workflow:
Checked that adding item defaulted to Generic classification scheme. It did.
In Library Settings Editor, I changed the default classification to LC.
Added a holding and it did use the new default classification of LC.

A step further:

Went into preferences in Holdings editor and changed default to Dewey.
Added a holding on a different title and Dewey came up as default.
Went to preferences again and blanked out the Default Classification field (which changes default back to Generic)
Went to add another holding classification scheme defaulted back to the Library Settings default of LC.