I agree. I do not find UB very problematic in practice. It is still certainly a challenge when writing security sensitive code to fully make sure there is no issue left. (also of course, model checker, or run-time verified code such as eBPF etc. exist).

But the amount of actual problems I have with UB in typical projects is very low by just some common sense and good use of tools: continuous integration with sanitizers, using pointers to arrays instead of raw pointers (where a sanitizer then does bounds checks), avoiding open coded string and buffer operations, also abstracting away other complicated data structures behind safe interfaces, and following a clear policy about memory ownership.