These debates come up every now and then when one company makes a factually incorrect assertion about another company's product in an effective advertisement. Last time, it happened when an effective series of ads strongly suggested that cable internet access wasn't scalable, and would (it was suggested) inevitably slow to a crawl as neighbors came on line, leading to humorously presented civic unrest (the ads were amusing and effective in promoting this inaccuracy). Well, sure, this could happen, but won't necessarily happen. Anyway, when the Cable folks complained, the DSL companies behind the ad trotted out the same old line "they're just made because the ad is effective and they look bad." Of course, this is just how marketing and often legal folks talk. It probably rankles an engineer more, because we get angry when rhetoric obscures the truth and leads to misinformation, especially about technical issues. This can be a weakness when engineers try to address the public - Andy Grove sure looked bad when he lectured everyone (entirely accurately) about how unimportant the floating point error was. Truth is, amusingly and engagingly presented lies can absolutely form the public's belief system. Marketers are great at this.

Anyway, I don't know what Mac's cost, so I can't evaluate the accuracy of the claim. But if Apple does have some decent choices in the sub $1K range, then sure, the Microsoft is making inaccurate claims, and Apple isn't peeved "just because the ads are effective."