Arguably, that is the notion that most people have opted to hold on to. That can be said to be partly true, but people soon forget that they(PCs) are slow(the Chromebook will boot in approximately 8 secs) plus the regular updates can prove expensive.
These devices might not be such a bad idea after all and perhaps the skepticism will die with time.
You should buy a Chromebook if you spend more than 1 hour a day on the internet. Plus, with Google apps, you can do things online you used to do offline. Even if you need your PC for Graphic Design or for some other reason, you should still have a Google Chromebook for the net.