SUMMARY
Titlebar colors are still broken with Breeze and Breeze Light combo.

STEPS TO REPRODUCE
1. Switch to Breeze and Breeze light.
2. Clone Breeze Light colors and alter Active Titlebar color

OBSERVED RESULT
Selected color does no effect.

EXPECTED RESULT
Color does change in the titlebars.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: neon-user-20220526-0948
(available in About System)
KDE Plasma Version: 5.24.5
KDE Frameworks Version: 5.94
Qt Version: 5.15.4

ADDITIONAL INFORMATION
Originally noticed on Kubuntu 22.04 with KDE 5.24.4, frameworks 5.93, Qt 5.15.3

It is possible to "hack" the color config file to force it to work (in ~/.local/share/color-schemes) edit BreezeLightMYCOPY.colors and DELETE the following lines:
[Colors:Header]
BackgroundAlternate=239,240,241
BackgroundNormal=222,224,226
DecorationFocus=61,174,233
DecorationHover=61,174,233
ForegroundActive=61,174,233
ForegroundInactive=112,125,138
ForegroundLink=41,128,185
ForegroundNegative=218,68,83
ForegroundNeutral=246,116,0
ForegroundNormal=35,38,41
ForegroundPositive=39,174,96
ForegroundVisited=155,89,182

[Colors:Header][Inactive]
BackgroundAlternate=227,229,231
BackgroundNormal=239,240,241
DecorationFocus=61,174,233
DecorationHover=61,174,233
ForegroundActive=61,174,233
ForegroundInactive=112,125,138
ForegroundLink=41,128,185
ForegroundNegative=218,68,83
ForegroundNeutral=246,116,0
ForegroundNormal=35,38,41
ForegroundPositive=39,174,96
ForegroundVisited=155,89,182

Seems to be a somewhat related bug: https://bugs.kde.org/show_bug.cgi?id=438273