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?
Not just you. Low(er) quality downloads are still a huge part of the torrent scene, see how popular most 720p YIFY uploads are even though their encoder quality is pretty garbage. Most people in general want a fast download and are viewing on a small laptop or even phone screen and don't give a rats ass about fidelity, LQ works perfectly fine for this. Even I'll grab a LQ once in a while if it's something my girl and I want to watch that night and I didn't plan ahead.
The desire for high quality uploads is more for people running home setups like Plex, where it's better to keep a HQ source file and have it transcoded to lower resolutions by your home server setup as necessary. They generally aren't storage constrained as an 8tb hard drive for a normal PC is fairly cheap these days. I'd wager maybe <30% of torrenters actually go after ultra HQ uploads based off seeder numbers.
Personally I stick to stuff that is at least 1080p with HDR and H265 encode preferred, because I archive most everything I download due to similar problems with internet speed. Over maybe 12 years of torrents I've amassed a hair over 5tb of content, and that's a LOT of movies l, it all fits on a single $120 external HDD.