PostgresSQL support for Windows on Arm has been requested with a PR.
PostgresSQL can be compiled and run successfully with https://commitfest.postgresql.org/37/3561/
Investigations are ongoing to add support for a build farm machine https://wiki.postgresql.org/wiki/PostgreSQL_Buildfarm_Howto
PostgresSQL is waiting on a WoA machine to be provided for their farm to build and run.