Its a forum where you dont need to be a registrered user to read. There is absolutely no way of knowing if any of them visit NSC or not.
This is the biggest BHAFC forum on the internet. If there was some internet forum where people on a daily basis gave you direct feedback on your workplace and your performances as an individual, would you not visit it? Perhaps not. But I'm willing to bet that at least 1 in 30 would.
As I've highlighted reading NSC as a guest is a deliberately unpleasant UX. Furthermore you don't have the right to reply. So, yes, there is no way to tell if Neal Maupay spends every day furiously reading NSC and lots of pop up ads but not being able to respond to any criticism directly. I'd suggest, however, that normal people don't do that.
I gave up using Facebook because of the absolute shit being posted by people I'd last met in the flesh 30 years ago and I had the ability to respond to that!