I have used this forum software before, And i know it is very possible to do a dark theme / a button to switch back and foruth. No idea why they have not used it yet.
True. It seems Razer is in TouchWiz mode, since both the Nabu and Cortex apps look like they were designed by Samsung. The Razer ID page though has a dark theme which makes it better and look like something Razer actually did.
I think the Insider forum is ran on Xenforo, Since the design looks a lot like one of those pages. Not 100% though, They may be using some other software that looks alike.
I like the dark theme because it is better so that way overnovernight we don't want our eyes to be hurt