Screen sharing from Mac to AppleTV drops out after a few seconds

Screen sharing from my Macs to my Apple TV used to work pretty consistently, then at some point in the last ~year it stopped working. I could click through on my Mac to start the sharing, my Mac screen would appear on my TV for a second or two, then the connection would drop, and the TV would show my AppleTV's screen saver. This seems to happen about 9 times out of 10 tries, to the point where I just give up on it, and my assumptions of Apple product quality.

This happens more with the Apple TV 4K (2021, model A2169, 32 GB, Ethernet), has continued through all tvOS and macOS versions since it started, including 26.0.1 (current).

I haven't noticed it happen with my Apple TV HD (4th generation, 2015, model A1625, also Ethernet, stuck on tvOS 18.6), but I don't use that one often.

This is probably actually a macOS issue, as it affects both my wife's and my MacBook Pros (2021 16" M1 Max, 2023 14" M2 Max), and my new Mac Studio (bought yesterday, 2025 M4 Max), but not my iPhone (15 Pro). I just got this error message in my Mac settings while checking this again.

This seems to have been reported many times by many other people, and none of the workarounds have worked for me

Screen Mirroring over Airplay no longer w… - Apple Community

I've tried:

• Rebooting both the Macs and the AppleTV
• Checking that there's no other traffic filters on the 3 different Macs
• Connecting via Ethernet or Wi-Fi, both the AppleTV and the Macs
• Connecting the AppleTV and Macs to the same wireless access point, and different, then same Ethernet switch and different
• Peer-to-Peer Wireless (setting on the AppleTV) on and off
• Rebooting the whole network
• Switching from IPv4 to IPv6
• Disabling the firewall on the Macs

As I'm typing this out, I tried again, it connected, and held the connection for about 10 minutes, then dropped, while I had Wireshark running. The 4x ICMP packets are interesting, the AppleTV is informing my Mac that the destination port is unreachable, I'm guessing it's referring to UDP 57949, the destination port on the AppleTV that the Mac was streaming UDP packets to. Happy to send the packet capture to Apple Support if it helps.

Can someone please point me to a fix that works, or release a fix in a macOS patch?