I had a 3rd gen Apple TV, but it had grown nearly unusably buggy. Still-supported apps would randomly crash or fail to stream, AirPlay would randomly fail entirely or fail to play video, streams/AirPlay would randomly stop, various operations would randomly take minutes to complete or time out.
Basically the issues as detailed here, though I had it more recently than the 7.6 software update: https://tidbits.com/2020/09/28/third-generation-apple-tvs-su...