It’s related to the buggy mess from end of Sep '24 power activation state being lost on hit (stun) when they added the 2 handed power swords and half-fixed the force and chain weapons, and nil fixed the power weapons.
The only weapon that has keep_active_on_vault = true properly set are the new 2 handed power swords (relic) after they reworked the flags for more conditions.
I guess we should be happy the keep_active_on_sprint flag is set huh.
TLDR Buggy mess since end of Sep '24 and only very partially “fixed” for some weapons; 5 months and counting.