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?
Pretty much the same here. the storage to quality ratio isn't a big enough difference to make it worth it to me for anything over 1080. 720p is noticable but I'll still use it no problem.