Your link doesn't really support your assertion.
I've noticed that you don't really think through the requirements, meaning, or the necessary logical consequences of your assertions. My understanding is that is what philosophy is supposed to be about, not about just making unthinking assertions and hand-waving.
The type of Idealism I'm most familiar with is Transcendental Idealism which I have expounded a great deal on in several posts, even photoshopping some lovely images together and coming up with several thought experiments to get the point across, however, it's not classical Idealism which posits the metaphysical nature of reality as "mind" because as
Transcendental Idealism points out, it can't be known. So I see classical Idealism as being as metaphysical as materialism. This is precisely my interest - the epistemological gap - not to posit what the thing-in-itself is as materialism does. I'm merely using the example of a simulation to demonstrate that. The point is for me an important distinction because it changes the assumptions we make about reality and we're less likely to make mistakes in judging what empirical results actually mean.