It's essentially the equivalent to western use of e-mail addresses, and e-mail spam was solved by a combination of technical hurdles, deep message inspection, bayesian statistics and penalization of anonymity.

I don't think e-mail spam is solved. It's largely just evolved to a non-competitive market where if you don't go with a major provider you'll forever be battling overzealous spam detection which flags your organization's email as spam. ...And you've lost some anonymity and flexibility.

It's solved for an average person. If you go with a major provider, spam barely exists at all. And even if you go with a smaller provider (like e.g. Fastmail), you barely notice any spam either.

Counterpoint: my burner gmail for account creation with 30k unread emails, mostly spam. Also so much spam gets into my university email accounts, much of it from predatory journals offering to publish anything and everything.

For the university accounts, I'd say only 80% gets trapped into the spam folder (my gmail is an absolute mess, however), but so does 5% of actual relevant emails and conversations, so I'm forced to inspect my spam folder pretty regularly which kinda defeats the purpose of hiding it from view.

I think he's more referring to the problem, where your email sent from a small(ish) provider is flagged by the big boys as spam.

Google is quite notorious for their ever changing goal posts regarding email reception. And if your mail is flagged as spam (and based on my own experience the AI behind it is not very intelligent) the only thing you get back is an automated response with completely and utterly useless "support" links.

So while spam may be solved on an individual user level, it's certainly not on the meta level.

No, it’s not. My gmail inbox is overflowing with spam to the point that I frequently miss important messages because they’re buried in marketing garbage.

That’s not even counting the business related ham google classifies as spam because the sender doesn’t buy email services from people that specialize in making sure marketing trash hits gmail inboxes.