The macOS app store didn't gain much traction but you're underestimating just how much of a cease pool the Windows app store is. Microsoft must have the resources to moderate that better. But based on my last test search of "Firefox" coming up with dozens of fake Firefox apps or "apps" that are "Firefox Guides" basically PDFs wrapped as an "app" etc... My only guess is Microsoft knows there's a truly abysmal number of legit apps so they just choose not to moderate it