Jellyfin is compatible with the Infuse media player on Apple TV. I don't have one but have used it on other Apple things and love it, it's actually a bigger issue with Windows because I haven't found anything nearly as good on Windows as Infuse is on Mac.
+1 for Infuse! But it only direct streams, so it's not the best if you want to stream over WAN.
I've had mostly a positive experience with Jellyfin on AppleTV. Have you tried it? Curious what's considered a dealbreaker for you.
Jellyfin has an Apple TV app called Swiftfin. It works decently well.