Spotify Connect is a real game changer. I tap a song on the web player and it streams it on our living room amp, which supports it natively. No apps involved whatsoever.
Tidal sorta has a connect feature, but I've found it to be really buggy (often wouldn't play or wouldn't tell the remote control device what is playing) and not as widely supported.
Apple Music is even worse since tends to rely on AirPlay, which murders quality and requires the remote to stay on the same network as the player.
That sounds like a minor quality of life feature, hardly a "game changer". Do you think this is impossible for other companies to replicate?
They are welcome to do so at any time of their choosing. It's only been an entire decade since the feature launched, I'm sure the competition will figure it out soon. For the most part, the only one I've seen that has more features than what is provided by basic google cast / airplay is ironically Youtube Music.