For me, the option "Both shift keys enable Caps Lock, one shift disables it" and "Caps Lock as Ctrl" have broken after recent updates. It seems to be a general bug in the advanced keyboard options, as a user on reddit mentions "Swap Caps Lock and Ctrl" got broken as well on 5.21.
Operating System: openSUSE Tumbleweed 20210217 (Krypton)
KDE Plasma Version: 5.21.80
KDE Frameworks Version: 5.80.0
Qt Version: 5.15.2
Graphics Platform: Wayland
*** This bug has been marked as a duplicate of bug 433265 ***
*** This bug has been marked as a duplicate of bug 433576 ***