Sorry, the statements were a bit disjointed.

iOS existed before the Microsoft Store. The apps developed were brand new. No backlash from a new SDK and platform.

Windows RT is closer to iPadOS though. For iPadOS, apps just worked since it’s based off of iOS.

The Microsoft Store only supported a new half-baked SDK that limited what applications were capable of. Developers already had Win32 apps and rewriting them with the new SDK seemed pointless just to support what seemed like a needless limitation.