The real reason appears to be that "physician educators" need jobs.
Also that bureaucracies have an inherent tendency to grow, and of course, to promulgate new regulations.
We have until next April to "certify", I think.
In my area, I have to travel to an obscure area almost 200 miles north to some "training site" in a shopping center, then go to an "examination site" in a different shopping center. At least, it appears it can all be done in one day!
Both the "training" and the "examination" organizations are private corporations -- for a program that the GOVERNMENT thinks is so important.