It'll probably be a 4k tv then? LG, Samsung, Sony, TCL, and Vizio seem to all have airplay support for TVs released recently these days. If Android TV it's easy to side load smarttubenext, but never bothered due to finding airplay convent enough.

Until then it might be worth checking out to see if you can get smarttubenext installed on your chromecast

https://forum.xda-developers.com/t/apk-smarttubenext-android-tv.3949377/