You could just use something like adguard to block DNS requests for telemetry endpoints.

Just use a desktop computer.

Digital signage displays are dumb PC screens in giant sizes, like you are looking for.

Just get any old TV and use the HDMI input and don’t connect it to the internet. The fears of it phoning home anyway even when you don’t configure wifi are overblown (almost no TVs can do this), as are the privacy implications. Nobody cares that you watch Severance and MCU movies. It’s sort of like people who tape over their laptop camera but leave the mic alone, as if 86400 photos of your face are somehow private and sensitive but all of the conversations in the room are not.

buy projector, laser one are good, some of them are quite dumb in a good way. mostly US owned, or Japanese. Any chinese one are full of "android tv with their own flavors of spyware"

Any TV if you disconnect from the network and stream via HDMI instead.

I was going to write buy Apple TV and never ever connect the actual TV to the internet, but:

- I am unsure whether modern TVs utilize ethernet over HDMI to connect to internet through Apple TV (I have no idea why Apple TV should allow this, but I don't trust Apple to not accidentally enable this)?

- I can only imagine nefarious five eyes reasons for why Apple released Apple TV that plays 4k60 exactly like the previous models, but now has 8 GB RAM, powerful machine learning CPU, and built-in microphones that are impossible to disable

So, apart from getting used prev gen Apple TV (and still having to trust company whose leader has to accept Trumps's lunch invite), I have no good advice.

That old kind that just had a VCR slot on the front.

Or a projector against a wall.

Find an old projector TV

I'd recommend a search, this gets asked at least once a year