I just don't have the time for it or well, I do, but I don't wanna put effort into mantaining ratios and whatnot. I have stuff to do that I enjoy more than be part of a internet club.
At the very least, you need to keep an eye on it. Just seeding can be insufficent because of speeds, competition and popularity of things you download.
Is it a lot of effort? Probably no but in my case any effort is too much effort. Is just not my thing. I admire the spirit but I don't have it in me.
My experience is that just seeding what you like indefinitely is not useful. You have to be proactive and find popular torrents to seed and accrue any meaningful upload amount.
The tracker I use has a bonus point system to encourage all seeders even of unpopular releases but it's slow.
I found that the perfect solution for my use case (music) ended up being Soulseek. I don't have much money for seedboxes or buying extra storage so I feel like I'm priced out of private trackers.