> they also maintain ratios

This can get stupid sometimes like when they're expecting everybody to keep over 1.0 when there are people with 10.0; but usually when they're doing that it's because it's a scammy tracker (all private trackers that you have to pay to join are scammy no exceptions) and they're trying to extort people who fall below 1.0 to give them money.

But expecting people to upload is part of the deal. That's not about being old, that's about being selfish. Non-scammy private trackers make it very easy, and some just concentrate on gatekeeping and don't worry about ratios at all.

Your basic point is very true, though. The way many private trackers have lasted is to stop letting people in almost entirely. To get into a non-scammy tracker you have to know somebody irl who is on and active, and they still might not be able to get you in. Or they will pretend like they can't - inviters sometimes get punished for the quality of the people they invite, and you think sharing back is something children do.