It's more complicated than that, Windows 95 would also check for programs intercepting INT 21h, sandwich its filesystem access routines in between and possibly

It's more complicated than that, Windows 95 would also check for programs intercepting INT 21h, sandwich its filesystem access routines in between and possibly call the old interrupt handler even when running from 32-bit programs. It's more optimized and more polished but it's still Win386 at its heart, and it actually makes sense a lot. The book "Unauthorized Windows 95" talks in detail about how it works.