as for this one "My comment – Something is motivating the DTCC to act and clean up the books"
This think the motivation is simply a service to their customers, Who did not react immediately to the chill and thus have aged fails to clean up. As they said in the future they plan to do a better job of communicating that a chill is coming to help their customers take action and avoid the problem this lift is meant to clean up.
It is easy to figure out what you believe. The difficulty lies in determining - is what you believe the truth.