I get the same errors on two Macs M7121-1331-p7. Site works up until you try to stream the actual movie. Shields turned off.
There is an issue with Widevine which is preventing video playback on certain sites like Netflix.
We’re aware of the error and are tracking it here : https://github.com/brave/browser-laptop/issues/10449
The new version is release today with the fix of this issue. Please update your Brave version.