Thanks for this history, I wasn't aware. It's an interesting point that if this is happening anyways by Apple's fiat, it's in the legacy CAs' interest to even further accelerate the mandatory timeline, so they can pivot to consulting services for their existing customers.

I do still feel that "that blog/publication that had immense cultural impact years ago, that was acquired/put on life support with annual certificate updates, will now be taken offline rather than migrated to a system that can support ACME automations, because the consultants charge more than the ad revenue" will be an unfortunate class of casualty. But that's progress, I suppose.