If “what security implications does xyz have” was easy to answer then there would never be another hack or data breach. The simple answer is that we don’t know. And it is very expensive to find out.
I'm indicating that "it isn't easy to answer" is the root of problem there.
It means that the engineering teams were incompetent in designing a system with a "narrow waist" security infrastructure. Then the solution isn't deprecating xyz but fixing the security infrastructure. Otherwise the same issues will surface again and again in the newer products.
