It was never underrated, just too useful. Every time someone invents an actually effective method of person-to-person file transfer, it gets used for piracy and blocked and shunned.
This. I've been working in P2P for 13 years. It's mostly a solved problem. All the new tech and noise are unnecessary. People think improving the tech will cause adoption but it's not the case. P2P remains fringe because it is hard to control and monitor. The friction is social not technical.
It exists on a knife's edge: incredibly useful and powerful to those who are in the know, but obscure enough to avoid heavy handed efforts to obliterate it.
I sometimes wonder how LLMs will impact this. They're much better at surfacing this kind of arcane knowledge than traditional search engines, and that risks increasing accessibility.
If accessibility gets too high, the ISPs could respond against it.
It's hard to monetize at VC scale, but that doesn't stop small-scale pirates and gray area business to use and make a living out of it.
E.g, in Brazil, Greece and (if you know where to look) even here in Berlin, it is not that difficult to find set top boxes that come with Kodi pre configured with a private tracker and some custom frontend to download movies and shows on demand. In Brazil you buy the box and you pay something like R$200 ($35) per year.