This talk overstates the problem.

I personally have run my own mail server for years, including for awhile on a residential DSL connection, using https://www.authsmtp.com/ to actually send mail.

I've also experimented with sending mail from that same DSL connection. Worked fine to Gmail, and Protonmail once I setup SPF and DKIM.

Try it out yourself!

Actually more like "the death of marketing spam emails" if this is anything like his article on the same subject.

probably important to reflect on :)