What you really mean is that Sky Go is incompatible with all modern web browsers. There is not one modern browser that it will work with so why the lie?
It does work with older, and insecure, versions of Firefox and with the security compromised Microsoft Internet Explorer. So why is it that Sky are relying on the discontinued Silverlight? Other companies can make their applications work so why is Sky different. That of course was a rhetorical question as Sky have never ever been concerned with customer satisfaction, quite the opposite in fact.