One would think, and common sense should dictate ... but I believe way too many people spend their money on what they think works or will work best for them, and they think what they do based on advertising, product reviews, or just word-of-mouth. I mean, just look at how much people in this country overspend on crap they really don't need (yes, I'm just as guilty). If people can be swayed to buy stuff they don't need, they can surely be swayed to a particular product that they do need even though it might not be the ideal product to suit that need. And once they do make that purchase, unless it's a complete and utter dog of a product, most will tend to continue to reinforce how 'right' the purchase was, mainly so as not to concede that they may have made a bad decision.
At least this has been my observation with products of all kinds -- people in general do not like to be faced with the realization that they are wrong. Obviously the degree to which this occurs varies from one individual to another; some are more willing than others to admit a bad decision, and some just always have to be right even if it kills them.
Add to that what drives the media: viewership and page hits. They're all going to tell and spin stories in ways that will maximize their audience. They love to pile on and kick someone when they're down almost as much as watching the mighty fall (can you say Charlie Sheen?). I think you'd be surprised at how many people get their information from a limited number of sources, or even just one source, and then consider themselves completely informed.
This is not to suggest that RIM did not have a major role in burying itself the last several years, particularly with their own horrendous marketing; but I believe their situation has been worsened by a media and blogosphere overly eager to rub salt in the wound and the dirty-laundry crowd who can't seem to get enough of it.