I worked at two companies 15-20 years ago that invested in top-tier QA teams. They were worth their weight in gold. The products were world class because the QA team were fantastic at finding bugs we developers didn't think of looking for because we were too close to the problem. We are too used to looking at the happy path. One key attribute to both companies is that it was dictated from on high that the QA team had…
I've seen developers writing tests with no assertions, or with assertTrue(true). Always green, with 100% coverage! The same people have been asking: why should I write tests if I can write new features? And then one senior QA comes and destroys everything. Once I found that if I press f5 50 times during a minute then backend will go in outOfMemory while spinning requests to the database.
This can be OK if the code executing without throwing exceptions is itself testing something. If you have a lot of assertions written directly into the code, as pre- or post-conditions for instance. But I'm guessing that wasn't the case here.