I recently found a guide to installing Pydio Cells on a Raspberry Pi, dated 6 March 2023.
I quickly ran through some of the installation steps, focusing mainly on installing the binaries, and was at least able to bring up the Pydio Cells initial set-up menu via a browser. It’s not clear to me if a separate pydio user is needed during install or if you can use the default dietpi user.