This is not a good invokation of Chesterton's Fence.

The Fence is a parable about understanding something that already exists before asking to remove it. If you cannot explain why it exists, you shouldn't ask to remove it.

In this case, it wasn't something that already existed in their game. It was something that they read, then followed (without truly understanding whether it applied to their game), and upon re-testing some time later, realized it wasn't needed and caused detrimental side-effects. So it's not Chesterton's Fence.

You could argue they followed a videogame industry practice to make a new product, which is reasonable. They just didn't question or test their assumptions that they were within the parameters of said industry practice.

I don't think it's a terrible sin, mind you. We all take shortcuts sometimes.