I've been in this line of work for a long time, and I'll admit its a huge factor. Webdev is a very fad-driven business, and I've seen numerous technologies come-and-go where they were hot, but not they are now super not. And to some degree this is logical, because you want people who can adapt to whatever is latest-and-greatest and not just a particular platform. But when recruiting it certainly helps.
Plus the old chestnut that 50%-80% of software projects are failures, and looking out for number one means resume-oriented development for the next job. You are probably better off with a failed project on a 'cool' framework than a successful project on an uncool one.