I have a very slow Internet connection (5 Mbps down, and even less for upload). Given that, I always download movies at 720p, since they have low file size, which means I can download them more quickly. Also, I don't notice much of a difference between 1080p and 720p. As for 4K, because I don't have a screen that can display 4K, I consider it to be one of the biggest disk space wasters.
Am I the only one who has this opinion?
I like to watch TV shows in the background where I'm not going to be watching the screen obsessively, so I have several shows in 480P or sub-480P. There are also some shows where the "official" HD versions are just awful (most 90s sitcoms) or the show was made for 4:3 and has a different feel converted to 16:9 (MASH, The Wire).
Going beyond that though, I spent years on a really limited connection (2.6m down/400k up) and my instinct for saving bandwidth and storage space is still there, along with my need to pay it forward since I ain't no leech. I've become fond of making what I call "Bonsai Encodes", where the files are small enough to be sent over damn near anything. With mono Opus and VP9 video you can cram 45 minutes of perfectly watchable content into a sub-25mb file that'll play in Discord, with VTT subtitles even (though those won't play in Discord itself). Looks a bit like watching it on an old tube TV, but it's watchable.