I'll upvote you for at least asking the question. But you get downvoted because your premise is wrong.

There are lots of organizations that support the ACME protocol. LE is the most well known, but there are others, and more on the way.

Existing CAs don't necessarily vanish with this change. They are free to implement ACME (or some proprietary protocol) and they are completely free to keep charging for certificates if they like.

The real result of this change is that processes will change (where they haven't already) improving both customer experience and security.

But to be clear there's no "one organization" in the loop here. You can rest easy on that front.