It works fine connected to an AppleTV 4k and and appleTV is the only smart TV software I'll use. It's smooth as butter, has no ads, and integrates with the rest of my devices with minimal setup.
Apple has their dark pattern approach to promote the Apple TV+ service. Netflix refuses to participate in the global search. Apple constantly injecting ads about their content into other content.
It can also serve as a front end for a Plex server if you run that. While this isn't "local files", it works well and serves a similar purpose. Note: there is a very fair, cheap monthly/yearly/lifetime subscription required for any advanced features but it's free to try. I pay $12.99 for the yearly subscription and I'm incredibly satisfied. If this reads like an ad, it's not, I'm just really happy with it.