IMO, if you're preparing/ ed to spend a sizable amount of money on a major electronics purchase (like say a laptop), you have the responsibility to preform the research necessary to inform yourself on the purchase.
You wouldn't buy a house/ car/ other major purchase without preforming research (or so I would assume), why would an electronics purchase of similar importance be any different?
There's no way you can research every single iota of information you may be presented with, especially if tech savviness is not your strong suit. If you get into a conversation with someone who *seems* like they know what they're talking about, you could be led astray.
I agree with you to a point on the research, but I think it's too far to say it's dumb people who get screwed, while smart people don't. It also kind of oversimplifies these kinds of incidents.