The point is an engineering manager is using software engineers as typing savers, too. LLMs are, for now, still on an exponential curve of capability on some measures (e.g. task duration with 50% completion chance is doubling every ~7 months) and you absolutely must understand the paradigm shift that will be forced upon you in a few years or you'll have a bad time. Understanding non-critical code paths at all times will simply be pointless; you'll want to make sure test coverage is good and actually test the requirements, etc.