Vanilla Qubes is IMO still not for average users: it still is complex and has a very steep learning curve. Conceptually, it’s pretty simple from a user standpoint, but users still have to be computer competent and a vast majority simply aren’t.
So while Windows support is certainly an issue—and an important one—maybe the Qubes Team is working on what they can at the moment. I really don’t know why this isn’t getting done, but the team has worked hard over the years and, to me at least, earned the benefit of the doubt.
I apologize that you don’t have the Windows support you need, but if it’s really important, I would encourage a donation earmarked for Windows support to incentivize work on it. EDIT: My apologies, but this is not the case. Because resources are limited, the Qubes Team does not work on specific projects for donors.