I'll admit, I didn't read the whole article as it quickly sounded like the guy wasn't quite sure what he was talking about, so I'll give my 2 cents on the idea in general.
Essentially I agree with what he is saying. I had a small discussion with Sid recently in the Skyrim thread about things we'd like to see implemented, and he was talking about a dynamic economy complete with taxation etc. I didn't quite argue against the idea, but I pointed out that that level of complexity in a system is a hell of a lot of work for something that happens beneath the surface, and could be mimicked instead in a much more expedient fashion. It's the same principle with what this guy is saying. You don't need comprehensive engines that can run deep and complex programs, you just need to be able to create your desired effect with minimum work or fuss. I have a buddy who works in the industry, and I remember him telling me once that one of his lecturers always used to say that there was no point creating some complete if you could just cheat to get the same effect. If the tech can be dumbed down enough to allow that, without compromise, then go for it.
However it should not be an excuse to avoid creativity. Skyrim is a good example of the pro's behind creating your own engine compared to reusing an old one.
I have to disagree with the suggestion that nobody cares about who makes an engine. People who follow the industry workings are always aware of the Unreal engine, and new developments are a big deal.
“It's a movie. If you are going to believe and be affected by an action film, you shouldn't go to see Pocahontas because you are going to think you are a Disney princess” Chloe Grace Moretz, what a legend.