> Dropped the test suite entirely, haven't had any issues since.

That you know about.

That bad test suites exist is unarguable.

Bad production code exists too, but we don't give up on writing production code.

You know all about it at run-time.

I knew a guy who used to wire down safety features on old gas stoves. He said similar stuff about how unnecessary these were. He died (along with his daughter) a year or two later because he disregarded what ski areas were and weren't off limits. Something he'd no doubt done before without any problems. You're fine until you aren't.

Why not write tests that make sense then?

It would definitely help in maintaining the code (not to mention not having to go through the entire code base when debugging a production issue).