Yeah, no. Yes, in theory undefined behavior can destroy your entire program. In practice? Not so much.
I do not care about bogeymen that exist in theory. I don't even care about bogeymen that affect your code. I only care about bogeymen that actually affect my code.
As a user, I do care when people who declare that UB is not a problem because "you just have to write good code" still end up repeatedly shipping apps and libraries with vulnerabilities in them. Which with C and C++ specifically happens all the time, and much more often than in languages with significantly less UB. The proof is in the pudding.
I do not care about bogeymen that exist in theory. I don't even care about bogeymen that affect your code. I only care about bogeymen that actually affect my code.