Indeed. Another example I have in mind is MIRC but both filled a void. I think there is little room for crypto to fill. Most of the world doesn’t have a need for it.
Torrents, P2P file sharing in general. I really don't get the argument that technology doesn't get adopted fast.
I don't see why that's self-evident. Decentralized applications get fast and wide adoption all the time, e.g. Napster.