I think this is the key mismatch in what Apple says and what it does now. With the Mac, they have ditched USB-A, SD, HDMI, Ethernet etc in favour of USB-C - a next gen standard that is only just rolling out (and not that well supported yet). They hail the Macs as being forward looking. The AppleTV doesn't support 4K, let alone HDR, DTS, Dolby Atmos/DTS-X - a standard that's been around for several years and has seen widespread adoption. Why is the Mac so forward looking while the AppleTV isn't even present looking?
There's a very simple answer. It's called iTunes and it's $$$$$$$ for Apple to sell you EVERYTHING from iTunes and make it 100% incompatible with everything else due to Fairplay DRM. Want to get rid of AppleTV and move to FireTV and have a lot of iTunes movies? Good luck. You can't play them on Kodi unless you remove the DRM somehow. Requiem used to do this quite nicely, but it only ever worked in Snow Leopard and older versions of iTunes. It still does work, but as of January, Apple no longer sends 1080p to older iTunes versions (only 720p now despite whatever setting you select) so it's not as useful as it once was even if you have a setup (say in VMWare) to use it. Lock you into their ecosystem and they have you. The more you spend on iTunes the less likely you are to EVER leave Apple the rest of your life (or theirs). Fortuantely, I got rid of all my DRM while the getting was good and moved on to FireTV and Kodi.
On the down side, the Kodi devs generally treat everyday users like garbage and don't care if things like skips in music occur over networks because they don't care about anything but whatever they feel like doing. I'm sure that's not THAT different from Apple either except for the fact that music has played back flawlessly on AppleTV since 2007 and Kodi STILL can't do it right unless it's locally attached (maybe it just doesn't like Mac servers?). But then AppleTV traditionally wouldn't allow any other formats (AVI, MKV, FLAC, etc.) and they never even put back features it once did have (e.g. AppleTV Gen1 had full album artwork forever before Gen2/3/4 had any kind of solution. Gen1 could play DTS music since it had flawless 44.1kHz output while newer models cannot even output 44.1kHz (the CD Standard!!!) PERIOD which makes it anti-High end audio even with Apple Lossless in use since it always has to turn it into 48kHz (and that kills any DTS signal, etc. encoding in the process). Kodi depends on the hardware you're using, but it generally will output anything the hardware will allow. I've also since discovered something (an addon) called CinemaVision that lets you sequence any number of ads, intros, trailers, cartoons, THX bumpers, etc. to play before the movie starts making it feel almost exactly like a real movie theater (assuming your playback screen is large enough). You can't do that on AppleTV evne with something like MrMC installed since it won't take plugins/add-ons. You CAN get full Kodi on there, but you have to have a developer account and they aren't free and expire every year. That's an expensive way to use Kodi on AppleTV....
Apple TV is great unless you want to stream pirate streams, in that case buy a fire tv stick or android box for kodi. Apple TV in the UK will have everything once Amazon allow a prime to app for it as it already has Netflix and Now TV etc. The new law changes in the UK have made streaming pirate feeds a bit more dicey as you could potentially be served up with a 10 year jail term. That law plus the previous internet privacy law (isp's have to record all website visits) opens a whole new can of worms over the next few years.
AppleTV is not that great (no Amazon player yet and it will never have 4K output with the current hardware). Pirating has nothing to do with it for most of us (I don't use any illegal streaming).
