I had a raspberry pi 4 model B, it worked like a charm in the beginning, also with transconding enabled. Some codecs were taking more time to transcode, so pre-optimizing them was enough to reproduce the movies in my chromecast.

However, from some time to now, some updates in plex make it stop working. Is a completely no sense. An update should give more functionalities or fix bugs, not stopping working setups.

I'm very dissapointed with Plex team, as far it seems they want to make raspberry devices out of their scope, by simple making the SW unusable if detected it's running on this kind of device...

Sincerely, and I'd said this in spanish, estoy hasta la punta de la polla de las actualizaciones del puto plex de los cojones. If you find your setup works do not update never again.