Even without a widget I can definitely see that with Netflix I am getting 720p on a 4k TV, even more frequently when watching childrens shows. I have a 200Mbps internet link, Disney+ plays 4k just fine.

Resolution on its own does not mean much. To me all that matters if it is visually ok.

It is not. It's very clearly not HD and we gigabit internet. Other services do fine. Especially rented HD movies that are streamed. So instead of using my TV for Netflix, I watch on my laptop with a browser plugin to set a proper resolution.

Right but the visual quality depends more on the actual bit rate than on the nominal resolution.

But bitrate doesn't matter if they've selected 720p for you.

As is commonly forgotten, 720p is "HD".

I think I’m missing your point.

What I’ve noticed: a Netflix 1080p is very much worse looking than the 1080p I get off Plex.

Unbounded bitrate on 720p video will always look rather degraded on a 4k screen.

I do not have dedicated TV. Just computers with big 4K monitors. I gave up on TV and replaced it with the computer some 17 years ago I think

We just have less streaming services and rent or buy the content we want to watch.

Internet provider may be throttling you on purpose. Do they sell TV as well?

Just wait a while. Your eyes will get like mine as you get older. ;)

You can on most TV sets and STBs. UI is a bit hidden, but you can.