Issue with Plex app for google tv?

Server Version#: 1.42.2
Player Version#: latest on google tv App Store
Sony BRAVIA 8 OLED (google tv) with Plex app (client to a QNAP NAS server) been flawless since purchase 15 months ago. Two weeks ago it started taking an age to load and to do any actions. Did a TV factory reset based on advice. Same story. Thought it might be a network issue and replaced the network switch that manages the TV lounge gear. No dice. Also switching the TV to wifi instead of ethernet didnt help. The spookiest thing of all, and maybe im too deep in this to understand (which is why im asking for help) is that by thinking I could bypass the issue by plugging in a google TV 4k stick to use the app there - but Plex running incredibly slow on there too (notably also google tv version). And Netflix fine. WTH? Have also rebooted the google nest network. We have gigabit fibre and all tests suggest that runs just fine. When I DO get Plex to talk to the NAS it runs high bit rate movies just fine over the home network. It just takes an age to get to the playing screen (minutes). Before I call ghostbusters I would welcome any suggestions and knowing whether there has been an update to the google TV app that is known to be problematic. thx!

Same thing happening to me on my Hisense.

Cleared cache and the app took about 2 min to load to the login screen so not an issue with the connection to my server.