I think your professor is missing a few things (or they haven't made it to this conversation so far):

Microsoft's campaign exhibits a lot of diversity - ethnicities, ages, roles. Apple's poster boy (singular) is a smart-alec white hipster. I didn't particularly care for the 'laptop hunter' ads but one of them included the line 'I guess I'm just not cool enough for a mac', which I thought was a clever dig at the snob appeal and pricing of the Mac products. It's also, I suspect, aimed at offsetting the grumbles of nativists about Microsoft's public support for H1-B workers - though perhaps I'm attributing too much vision to CP&B there.

More importantly, most of the commercials emphasize what people do with their computers - they run busineses (tattoo guy), study or make movies (laptop hunters), or grow up doing creative things (Kylie, the terminally cute little girl). The Mac guy just stands around saying how much better he is because he's a Mac - he doesn't actually do anything. So the CP&B ads mostly establish a direct connection between customer's goals and the product they can use to achieve them (Windows and the computer it runs on).

The Apple 'tech' commercials (this is a Mac/iPhone - look, you can do this, this and this) are much better in that regard, but they do present a solution and invite the viewer to consider how it might solve a problem or ease their routine. I think think it's interesting that the MS ads are built around the idea of the user articulating the goal first and then exercising or expressing a choice to do it with a PC. In narrative terms, they establish character first and then offer (their) technology as an aid to that.

Finally, the MS ads show Windows running on a variety of different hardware - premium to be sure, but that variety carries connotations of choice, flexibility, and mutual confidence among manufacturers in Windows, whereas Apple is an all-or-nothing proposition. You want to go Mac, well say goodbye to your existing hardware whether or not it works...not an easy decision in recessionary times.

I'm actually pretty impressed with CP&B. Even the Shoe Circus commercial with Seinfeld was clever: by playing off the dorkiness and incomprehensibility, and ending with an image of a departing bill Gates (but with a hint that new things were in the pipeline), it effectively leveraged the existing preconceptions about Microsoft and used them as a pivot to direct attention towards what was coming next in the campaign. It was like one of those movies where there's an opening scene which makes no real sense until later...'all will be revealed'. Its purpose was to engage people's attention, at which it succeeded very effectively. And for those who say Seinfeld was way out of date - for one thing, the show is still in syndication and regularly advertised (staying power) and for another, isn't that what people were saying about Windows, that it was past its peak and washed up? And yet Seinfeld is still a big wheel in his industry and is about to launch a new series...which had already been in the works for several months when he appeared in 'Shoe Circus' just over a year ago. Matter of fact, I bet any time you see a computer in that series it'll be running windows 7.