Why won't Apple TV play the MP4 film I bought from ITunes in 2015?

So now that I'm on a macbook pro running Ventura I no longer have Quicktime available to play my MP4s and have to resort to the bloody Apple TV application which is now standard; when I click on the mp4 file in my 'library' I then am entered into a living **** of a spinning wheel in perpetuity until I force shutdown my mac and restart. WTH??? Why can't an Apple app that is SUPPOSED to play media content NOT play an MP4 downloaded onto my laptop? God forbid (or Steve Jobs) you watch content that Apple didn't create on THEIR streaming service...