I think these are just technical excuses, but the real answer lies somewhere in the fields of politics and economics. If people in charge are to make a decision – then us tech nerds are going to migrate and refactor 1000 applications and update 20 years of byzantine code mess. I saw entities so large and boring they can barely move one step – changing rapidly and evolving once their economic stability is at stake, and this is a great example of such a disruption which can push them into chasm of change.