If you've ever tried to do even the most basic of UI's in game engines, you'll quickly see the truth in that statement.

Even "easy" things on the web like text input boxes, scaling for different resolutions while keeping text crisp, and scrollable content areas are much harder in a game engine.

I've done both for a living.

So your argument is, for YOU :- game programming is less productive than building a website. That's fine then. I wouldn't disagree with someones personal experience. I thought you were making a general argument that applies to everyone.

I was merely saying I learned its less productive by actually developing both video games and web applications instead of simply reading about it.

It may be personal experience but it doesn't change the fact that you're working on a much lower level in a game engine with long iteration times while a browser reloads almost instantly and builds on layers after layers of abstractions.

That argument still applies to everyone.