Sounds like they did a great job, awesome.
Don’t Apple recommend not doing at the App level but for individual video assets?
We plan to do this because it guarantees less switching. What Apple suggests is for devs to strategize mode switches so that they happen the least amount possible. People tend to change channels a lot while watching TV vs putting on a 2 hour movie. If we only switched when video played, it would be a lot of toggling for Channels users. Since we 100% know for sure that none of our video is HDR, we’ll switch when the app starts, so that there’s only a single switching moment.
And again, we suggest that you live in SDR mode by default, like you said you planned on doing. If that’s the case, there will be no switching at all.