But in that context, 50k PGP users is arguably "almost no one." If we guesstimate 4 billion Internet users, that's 0.001% of all users.
I think the point is not that PGP is impossible to use, I think the point is that PGP is not appropriate to scale to the global Internet the way other encryption technologies have.
PGP has an outdated and confusing UX, a broken threat model, and is extremely bad in many respects. But it does have users, and for some people and some tasks, it works better than alternatives. (My use cases: exchanging routine work email with other nerds who have it set up, share confidential documents.)
So, while we shouldn't minimize its very major problems, we shouldn't pretend that its user base does not exist and that it's not addressing at least some use cases.
PGP remains wildly popular on Tor cryptomarkets, an area where users assume server compromise will happen yet still decide to transact using encrypted messages.
Don’t underestimate a technology gaining popularity in fringe communities with young user bases, often from non-technical backgrounds. Kudos to companies like Keybase and Protonmail for investing in PGP’s future.