You're focusing on Flash. I am not. The same applies to all buggy projects.
Knowingly introducing a change with consequences that aren't just mere crashes, but data corruption, for end users - if you cannot see how that is wrong, I have no idea how to help explain it.
Yes, of course, the performance achievement is worth having. However, not at this cost. Not without first adding some audit logging. Not without giving developers time to fix that. It is an incompatible change in the ABI.
I can read the man page as well as you can. Sure, the applications are buggy; that does not give one the right to corrupt user data. Such changes need to be phased in carefully; not in a "I am more righteous than you" style. It is bad enough when it happens by accident; intentionally, it is malpractice.