@eobox91103 Perhaps you have donated to the site? Other people do report the limits on simultaneous leeching.
And, yeah, this can snowball in both directions - you have enough ratio, so you comfortably download more and right away, so you can just keep seeding it and maintain the ratio. And vice versa - when your ratio is low, you download a few files, or hope for a freeleech - then, when it doesn't happen even your best attempts at seeding won't be enough.
When some people have 10x the upload speed or more, and have external IP addresses, meaning people can connect to them, giving them maybe 5x more peers, looks like only large, 50-100GB torrents can leave enough room for everyone.