Another problem with Boox is the disregard of the requirements of the GPL family of licences. I've been interested in some of their devices but won't touch them due to that (and now due to the issue you stated - though I was unaware there was un-disablable “telemetry”, I'd have to look into that if they ever did something about the lack of GPL compliance).

they didn't, they even said something like "lol we don't care, we will never make things open source".