The most extreme examples of the problem are tests with no assertions. Fortunately these are uncommon in most code bases.
Every enterprise I’ve consulted for that had code coverage requirements was full of elaborate mock-heavy tests with a single Assert.NotNull at the end. Basically just testing that you wrote the right mocks!
I like them a lot. Sometimes I use it as an agenda to sell an idea in a meeting. Othertimes I backport them after a decision has been made. It’s the context that drives a decision that easily gets lost to time.
I’ve been burned when a technical decision hurt us down the road and no one could really remember why we made it to begin with.