Well that's not correct.

Engineers are great at developing a product.

But having someone at the end who's using the product and insisting on consistency because he's anal-retentive and a pain in the ass will mean the product is consistent with the evaluator's goals.

macOS used to have a lot of underlying features that worked consistently no matter which app you were using, and Apple destroyed that.

Either Jobs was having an effect, or it's a damned strange coincidence that the severe reduction in consistency in macOS started just at the point that he died.