Who sold you that notion?
Matlab is proprietary glue holding together modules written in Fortran, C, C++, Java that allows the adhoc inclusion of DLLS put together by graduate students on the fly.
In what universe is any of that "memory safe"?
Like the matrix handling, plotting, and other modules dragged in from the 1990s standard FORTRAN library era.
Don't get me wrong, I have placed a lot of trust in those kinds of numeric libraries since the 1980s - NIST and other national labs code and review to a high standard - but they weren't then and aren't now "memory safe" just very probably and mostly bug free.
Unless they were, say, rewritten in Java .. and that's a whole other big ball of issues .. translated code.
I'm happy to play along and agree that the JIT compiled 'Matlab language' parts of Matlab are memory safe - but to the best of my experience with past versions that's just the glue portions - the reason so many people use Matlab is for the chunks that get glued together.
They can still have bugs, memory issues, be called with parameters that cause resource blow outs and aren't "memory safe" in the sense that modern managed languages are.
Matlab is exactly as reliable as well written Fortran and C code can be.