This is really presumptuous, and makes a leap from correlative to causal on the back of a couple of blanket assumptions.

The first is that there are better things to do than blog: based on what? If someone feels the itch to write about something they really care about, and doesn't want to bother with more formal methods of publication, I think that blogging is one of the best things they can do with their time. It is not like they are producing nothing; they are producing something that will -- hopefully -- propagate ideas and critical thinking. This sounds like a very good thing. Not all problems that are looking for an answer will have that answer found in a block of code; sometimes the wetware needs to be refactored.

The second is that people who blog more than infrequently are apt to be technically rusty, and should be subject of suspicion. This make me suspicious of those who would assert that. Again, based on what assumption? I agree with the claim that if they blog more they have less time for other things besides blogging; rollover minutes only work on some cellphones. But to claim that because they blog more they know less; this is quite an extraordinary claim. It wants to lump everyone who blogs a lot in with the blowhards. What if someone has a lot to say, and thinks it is important to get those ideas out? It sounds like you would tell that person to shut up and get back to work. I worry about the consequences of this.