Gee, I seem to be the dissenter here
Cases (some inter-dependent), with proposed actions;
1: @font found in HTML pages
1a: discard
1b: Move to (specified) CSS (Link updated if to a
new CSS)
2: @font in one or more CSS
2a: @font with no font-family usage of said font; Delete entry
2b: @font with embedded fonts; keep or Delete both
2c: @font (assumes device supports) without embedded ; Warn or delete
3: (bogus) font files without an @font; delete
4: font-family calls to a Font face (other than (Generic) serif or sans-serif) without
a SET of @font (Normal, Bold, Italic, Italic-Bold) statements; Warn if missing (what do you do about never used face versions)
I do use 2b and 2c @font usage on occasion .
1b would be my choice for those that do not violate 2a