in low level
Except the issues with poor cryptographic security Mike is talking about have only been observed-- so far-- in tools written in Java, Javascript, and Python in our ecosystem. None of these are low level languages.
You are right in that I should not have used "low level" for but type unsafe, since there are high level unsafe languages, like Javascript or Python. Java is type safer and Scala is even better, and that is what Mike said.
Added:
Not using compile time checks that type safety gives is pure arrogance.
BTW what about the heartbleed bug in SSL was it not in Bitcoin core?
Unfortunatelly you only use your intelligence to pinpoint inaccuracy in my sentences.