Netflix and YouTube have started using it this year, but with so many devices out there that don’t have AV1 hardware decoding, my guess is it will be a long time before any platform is exclusively using AV1. I’m no expert though.
Infuse has AV1 support now, although not for HDR videos I believe. Software decoding works almost as well as hardware, and I’m sure Infuse will continue to improve their decoding as the format becomes more popular. Hardware decoding is more important for mobile devices, as it uses a lot less power than software decoding (much less of an issue for a device like an Apple TV that’s plugged into the wall, instead of running off battery).
But the rumours say a new Apple TV could launch in early 2024, and that it’s going to be cheaper. Depends if you can wait 6 months, or if you want the Apple TV now. There’s always going to be a new model on the horizon