"It's very possible that I am overrated or that I am overrating myself. But it seems to me that the title of "most overrated living economist" would almost have to belong to a Nobel Prize winner. After all, to become overrated one must be highly rated in the first place!I considered the point in the first paragraph when I was writing the post, but I don't have the impression that any Nobel laureate I know of is overrated. Maybe they are overrated relative to each other - to take two I like as an example I think Krugman gets more attention relative to Stiglitz than he deserves. But I have a harder time coming up with one who is clearly overrated. I don't know, I don't generally think in these terms about them.
I recognize that a lot of people have strong feelings about the norm against saying bad things about dead people. But it sounds to me like you agree that Buchanan's work is overrated. So in the grand scheme of things, I'd say that you and are have a roughly similar opinion of this matter (to wit: Buchanan is overrated) and it would be wiser to spend the day objecting to the people who were lauding his (overrated) work yesterday than to my tweet."
But as for the second paragraph I want to make clear that I do not, in fact, agree with Yglesias on Buchanan. If anything Buchanan is underrated and not as widely read as he ought to be. Maybe I am "roughly similar" to Yglesias in where I find faults in Buchanan's ideas, but I really don't have the sense at all that his work is overrated so I can't imagine how I'm "roughly similar" on that count. We could narrow this down considerably and say something like "among the people who affiliate with public choice theory and who regularly accuse anyone who disagrees with them of romanticizing politicians, I think Buchanan's work is overrated in its significance". But: (1.) that's so narrow a claim it's not really notable, and (2.) that's more of a statement about that narrow group of people than it is a statement about James Buchanan.