CHEF-KOCH, being a Chinese, I must tell you it is not the case. In China most people uses Tencent QQ which is a proprietary protocol, other messengers that some people uses are also proprietary. The only Jabber compatible application is Google Talk, however due to the fact that China government blocks Google services, only very few people uses that.
In Hong Kong, most people uses MSN or Whatsapp/Line, only few uses Google Talk, and no other Jabber public services.
In Taiwan, it should be still MSN or Yahoo Messenger.
Don't think that Jabber is popular worldwide.
And from my attitude, why prevent porting of Miranda to other platform with similar API and still have a large user base? It is certainly not a waste of time.
I must say that I also hate Windows 8 a lot for the touch-only-friendly interface.
Giving money for bug fix or development of particular plugin are only projects of individuals, not on behalf of the Miranda IM team, it does not make Miranda IM commercial, so don't treat it like the commercial IM products.