When I worked on a big c++ codebase I found them essential for both ci/cd systems and actively debugging an issue. The valgrind suite of tools like cachegrind are very useful for both troubleshooting as well as classic static analysis and I heartily recommend investing some time in learning valgrind if you're writing c/c++ code for a platform valgrind runs on.

On the other hand commercial tools have been more of a mixed blessing but that is probably because every time ive seen them deployed the budget hasnt included sufficient engineering time, training or prof services to cut down huge numbers of false positives.