Cured zombie villagers do not reduce their prices with repeated curings. You get the initial reduction from the first curing, but after that prices do not change even after repeatedly reinfecting and curing the villager. Playing in a non-multiplayer world on Nintendo switch. Cheats are enabled, experimental features are not.

Note: this was tested using zombie villagers spawned by a mob spawner, which was obtained using commands. This same method has always worked for me in the past.