The Internet Archive should have plenty of public domain movies.

Not exactly what you’re asking but you make me remember the animation films from blenders: https://studio.blender.org/films/.

Might also try your local library and see if they give you free access to hoopla and kanopy!

There’s a lot on PeerTube. You can search on sepiasearch.org and filter the results by license. fedi.video has a bunch of uploaded PD/CC videos.

vodo.net used to host loads of CC movies.

Most of the ones on this list are probably available on archive.org/torrent/web to download.

Some really nice films/animations mixed in there.

(From memory, Mark Thomas, The Yes Men, California Dreaming, Couchsurf, A Grain of Sand, Crazy Golf, and I Think We’re Alone Now would be some good starters)