Apple has been pretty tight with AirPlay video, so it can keep people on its eco-system. Microsoft started adopting Miracast (which does work with Roku) and Google has shifted to the Chromecast (which does not work on Roku). I'm able to play/send files to Roku in 3 ways, 1st of which I believe is mirroring, it's not entirely clear yet.
Jan 19, 2016 AirPlay not working, how to fix AirPlay and AirPlay Aug 20, 2019 Ipad2 AirPlay mirroring not working after… - Apple Community
Method 1: Turn Off the Bluetooth to Fix AirPlay Mirroring Not Working. So that it is difficult to mirror iPad, iPhone to Apple TV. To solve this issue, just keep reading. Method 1: Check the Apple TV Updates. The first thing you should do is to check your Apple TV updates. If you don't update it in time, it may cause your Apple TV AirPlay
Dec 11, 2018 Airplay Not Working? How-To Fix - YouTube Jul 12, 2016
Nov 30, 2019
Nov 02, 2018 AirPlay Not Working? How To Fix - macReports Apr 21, 2020 [6 Solutions] AirPlay Mirroring Not Working Check the AirPlay Device. This could sound silly but it can be easy to skip such small things from … How to fix AirPlay problems - Macworld UK Airplay without mirroring isn’t working Another change in iOS 11 that confused AirPlay users was the fact that the ability to Airplay without mirroring disappeared. After upgrading to iOS 11 users