Some videos from Mac Photo app not visible on Apple TV 4K

Thanks for the suggestions, but neither apply.

In regard to your first suggestion, I am not referring to the TV app/Home Videos. I use that for videos I have created using multiple files. I am referring to the Mac Photos app and have ensured that the correct albums are selected, and "Include videos" is checked.

In regard to your second suggestion, I am not interested in using the iCloud function. I would rather my extensive library (20,000+ files) be on my Mac and back up drive. Home Sharing is my preferred method for accessing them from the Apple TV and it works well with the exception of my iPhone X video files for the last couple of years. If I look back through history, some due show up and they are the same file type.

UPDATE 2 - Just out of curiosity, I also compared iPhone X videos files that are visible to those that are not. I see no discernable difference, other than variations in file size. They are all format HEVC. This is really perplexing. Why are some available to view on the Apple TV and others aren't?

There seems to be no relevance to size or rate. The frame rate of all the videos is 59.99 or 60 FPS. The size of files varies. For example - a 15.5MB file does not show up, whereas a 150MB does. Another file, 400MB, does not. There seems to be no "cutoff" size that the Apple TV cannot display. I do not know how to check dynamic range, color gamut or codec. Given that all the videos in question are taken by the same device, I wouldn't think there would be much of a difference, but I am not well versed in video files. Also, the files are viewable if I AirPlay them, so they shouldn't be outside the range of what the Apple TV can display.

I appreciate your ideas though!

I found a Reddit post this morning that states Apple TV 4K does NOT support HEVC through Home Sharing. Link below (hope it is OK to share here - if not, delete it.) If this is the case, it kind of answers my question. However, I do see a couple of HVEC videos via Home Sharing, so I am still confused. I upgraded my old Apple TV to the newest 4K model specifically so that I can Home Share 4K video. What a disappointment.

[Link Edited by Moderator]

UPDATE - I have tried logging out/in of Home Sharing, as well as reset my Apple TV 4K back to factory and updated to the most current software version. I still don't see my iPhone X videos.