Well yes an no and here is why. Smart developer already knows this for at least couple of years (yes it's even more than that, I was being nice) and you could make the same amount if not more with Themes as well. This will affect only people who don't know more than just HTML and anyone who's not in CMS game. Very simple math :)

Profit for some is reduced true, but time to make sites as well. Why would anyone start anything from scratch when there are so many free Themes and Frameworks out there? In my opinion if you reduce time you are actually making more money. Think about it.

Cheers,
Emil