OK. But still don't throw that former employee under the bus. Your attitude should always remain 'there is room for improvement' and not 'this sucks'.

One thing to keep in mind is that technology at almost every company you will ever work for will be held together with some combination of duct tape and bailing wire. I have seen tables with no normalization whatsoever that support tens of millions of dollars of revenue. They key factor with IT is that it needs to work. And since these things tend to grow organically, almost none of them are optimized.