Apple does not care about anything that happens outside their ecosystem (and why should they?). If you want to play in the Apple world, you need to buy Apple stuff. You can ascribe all kinds of sinister motives to this, but it’s mostly for practical reasons: why would they invest money, effort and time into supporting products from their competitors when it brings no benefit to them?
By the way, to build and test Windows plugins, you need a Windows system. Why should it be different the other way around?