[bluGill]

Many reasons.

There is a long tail of exceptions to my statement, hard to find things that escape notice for years.

There are a lot of security issues that are not really memory safety as we are talking about here. (many are memory safety in a way that has nothing to do with getting your allocate/free wrong - using uninitialized memory for example). Some of them are subtle new attacks that were just discovered and now need to be mitigated.