Why “Write Tests. Not Too Many. Mostly Integration” Is Bad Advice

This author didn't really refute the quote. He didn't support his contention that we should write lots of fine grained tests.

Having a lot of tests can lead to undesirable outcomes, for example bad tests (tests that test the wrong things, that test the correct things wrongly, that aren't actually testing the code but something else, like library code or compiler output) and code that is structured poorly to accommodate testing rather than to accomplish a thing.