Maybe. I was a kid so probably was given crap equipment anf cheap film and likely didn’t treat it well. But the principle is the same. Having deeper shadows that preserve detail, and brighter highlights that aren’t blown out is what, for me, evokes a more visceral response when watching content, whereas Increasing the number of pixels from 1080p to 4K doesn’t.
First, good job on not having a smart TV. They’re truly awful.
I would de-emphasize the actual resolution benefits of 4K. Most of us don’t sit close enough to notice the difference.
For me, it’s about high dynamic range (HDR).
For example, when I was a kid, I was always annoyed by how the photos I took of what I thought was a gorgeous landscape, and then developed the film (yes, I’m an old) it always looked horribly bland and drab.
Watching 4K content on a TV for the first time was like looking at the beautiful landscape again. (It actually was - Netflix’s Marco Polo had the most stunning vistas!)
You may want check out Infuse for the AppleTV. I have found it fixed every audio drift and video jitter concern that I’ve ever had with Plex or Jellyfin.
You can point it either directly at an SMB share, or a library hosted on Jellyfin or Plex. The advantage of this is it caches the artwork in the library, not on the AppleTV, because the AppleTV will periodically flush its local cache, leading to long re-fetching times and waiting to watch things.
I have no recommendations for the Chromecast.