I think this is correct about sprinters and is likely exascerbated by the fact that since the 90s, we have been accustomed to most Grand Tours (and sometimes entire seasons) being dominated by a single top sprinter. I was in some debate yesterday about Cavendish; I was arguing that while Cavendish hasn't been the dominant force he was in say 2009, he has been there to mix it up in some sprints over the past couple of years and has managed to win a few (and was usually placing near or just above Groenewegan in those sprints). His pulling of a stage win (and maybe more) wasn't particularly surprising to me, but some people perceive that Cavendish has done nothing over the past couple of years to suggest that he was still capable of winning a Tour stage. I think Gaviria belongs in this category too, and it wouldn't be the strangest thing in the world if he pulled off a win in this Tour.
Though many people would point to Phillipsen, I actually don't think that we have one sprinter right now who is truly head and shoulders over the rest. Phillipsen, 26, probably is the best of his generation, so I think a lot of people feel like he (or maybe Jakobsen, 27) *should* be dominating the sprints. Historically dominant dudes in their 30s (almost 40 for Cavendish) being competitive in sprints and pulling off wins feels wrong to people, even though those guys have been present at the pointy end of races all along.