They both work, its just the odds are vastly higher of finding a library for circuit rather than micro and there's probably ten circuit python users for every micropython user. Although I "have to" use both.
I thought that was interesting to throw in support of the less popular but wider range of hardware choice for microcontroller python and not even mention the other more popular option.
(Side note what's up with UF2 firmware upgrades not working on ESP32-S2 chips, works on everything else, must be an interesting story behind that)