I don't know. I've played games where the engine had no name, and games where the studio-made engine had a name, and games where they licensed an engine and made it work. And I don't think there has been any kind of a trend in what games I've enjoyed more, or even which ones had better rendering. This sounds like one of those things that doesn't really matter, but if you've gotten used to doing it one way, you think it's the right way.