That works... for now.

It'd be trivial for them to introduce some sort of network connectivity check that would need to be completed before audiovisual signals come out of the device.

I'm pretty sure they already have that in the pipeline. Why wouldn't they?

I got a used Sceptre TV (https://www.sceptre.com/TV/4K-UHD-TV-category1category73.htm...) and I'm extremely happy with it. No "smart" features, no bullshit, no slow menus, just a set of 4K@60Hz HDMI ports (newer models do 4K@120Hz) with ARC and CEC and a comprehensive set of display options.

I do the same with my Samsung Smart TV but after a couple of months it stops playing videos from the USB drive or stops recognising the same drive. All I have to do is to turn off and unplug from the mains for 10-15 minutes and it starts working again!

I agree wholeheartedly to the first point, but then why undo that by using a set-top box that only works after phoning home? I'd rather the manufacturer not even know my IP address, let alone get a full login.

One step better: never bring a tv into your home.

It’s called an idiot box for a reason.

My life has improved dramatically without one.

Obligatory: “but they can run Ethernet over HDMI!”

Ignoring, of course, that no implementation has ever been observed in the wild, for purposes malicious or otherwise.