> This step was announced some time ago, and since certificates usually need to be replaced frequently

Most people will buy certs valid for a few years, or around a couple of dozen Chrome-releases, and forget about them until they expire.

From my experience, among the things deployed in the world of IT, I would argue they are among the things replaced most infrequently.

So I'm curious... What makes you say certificates needs to be replaced frequently? What's the use-cases you are referring to?