Being able to find, download and seed old series and movies.
Nobody ever stays seeding anymore because big private trackers make it all about ratio and small ones simply don't have to userbase to support "old" series.
Back with RARBG I had every season of that 70's show and had around a ratio of around 50. For old scooby doo, red green show, Mr. Rogers, Tom & Jerry, some cartoons from when I was a kid, etc... Now it is difficult to even find a lot of that media, much less have a good ratio from it on smaller private trackers where it might get 1 download per 6 months or so. There is absolutely no incentive for keeping around older media. If you want to get in good in trackers, you HAVE to pump and dump the most popular torrent of the week once a month or so to get a good enough ratio.
For example, on SceneTime I have a ratio of like 0.1 because it simply doesn't have users. However, they assign bonus points based on how long your torrent is seeding, if I am not mistaken, so my site "effective ratio" has gone up to 2 because you can spend the bonus points to add "upload GB" to your account if you are keeping alive "unpopular" torrents.
I like the trackers I'm in that have a point system that awards indefinite seeding and makes it possible to have a decent ratio even if you can't ever actually seed because of people with seedboxes.
Wdym all seedbox users stealing your ratio?
Some can't even participate with homeservers due to laws or don't even autobrrr through their whole wishlist.
The other tracker is much smaller and I prefer to not mention the name in public. If interested send me a PM.
Edit: The RARBG stuff should still be connectable over DHT and other trackers.
I also share the rarbg db so users searching for the rare unicorn in the database might choose to connect to yours over a magnet link.