“Not willing to make it universally available”…?
Here’s a link listing the literal hundreds of devices that support the Apple TV app. I’d recommend checking supported devices next time before signing up for a service and make sure you have one.
https://www.apple.com/eg/apple-tv-app/devices/
And here’s a link on how to cast Apple TV content from the Chrome browser.
https://www.lifewire.com/cast-apple-tv-to-chromecast-5200829
If after reading all of this, and you actually get to experience the service, and you still don’t like it, maybe then you can come and complain about how bad the streaming service is. But until then, making a “wOrSt sTrEaMiNg sErViCe” post because you can’t figure out how it works isn’t going to bode well.