As others have mentioned, the websites tend to be limited both by resolution and functionality.

My TV supports CEC(most do these days) which will pass the remote input onto the devices connected to it, like a computer. Which means with Plasma Big Picture I can navigate with my remote, and any app that supports navigation with simple arrow key input would work great.

Unfortunately, the streaming websites, last time I tried, absolutely suck at that and assume you are navigating with a mouse.

Many streaming service websites limit browser streaming to 720p.

That only would launch them and probably won’t support remotes properly.

I'm wondering what I've done wrong with KDE Connect as I could never get it working on any device across 3 different smartphones

The article actually stated that the featured is untested.

Controller support exists, but getting TV remotes to work over HDMI CEC is still untested.

You're absolutely right, that's just me not wanting it for Jellyfin on those grounds.

For mainstream users, I would assume that Linux being unable to run streaming services at full quality would discount it as a serious contender as well.

MS do sell Atmos (and DTS:X) support as an individually licensed thing, threough Dolby Access and DTS Sound Unbound on their store.

I do wonder how it could work in Linux, as well as getting things like commercial streaming services in 4K.

Presumably some sort of black box hardware would be needed (for the super top secret Widevine L1 shit), the manufacturer of that can pay the Dolby fees, and then just some basic open source code to call the hardware features.

Yeah, it's just what would work for me once I cancel Netflix Premium Plus with Reduced Adverts.

It's basically HDR (the 10 bit display kind, not the Half Life 2 kind), but with more metadata.

What I find is that if you have a Dolby Vision capable TV, it will be already calibrated to something that looks good, rather than you having to fuck around telling it how bright "paper" is or some shit.

HDR displays are surprisingly tricky, even without Dolby Vision or HDR10+. Especially if you're mixing SDR and HDR content on a display. I tried it a few years ago on Windows and it was flat out awful. I think they've fixed a lot of it up now with Win 11, but even they took their damn time over it.