I’d be interested to know the status for the player apps on various platforms. For example, this is a nonstarter for me until it supports Google TV and iOS/iPasOS.
Yep, it's definitely easier to get third party clients to implement your protocol. Kodi you can write your own plugins for, Infuse... requires their devs to care about your implementation. Chicken, meet egg?
That said, I also fully admit I have no knowledge of your codebase, nor any knowledge of how extensive / complicated the jellyfin (or any other comparable media server) client api looks like, and I assume you have a better idea!
Best of luck with this! I hope it succeeds!
I want to focus on features before writing more clients, I hope to write Chromecast support in less than 6 mounts and google tv in less than a year.