I had to take this article with a grain of salt as I felt it to be negatively biased. If the Ludwich von Mises Institute had a least favorite person, Keynes would be their man. In my opinion the author was not very objective and had it out for Keynes.
The author paints Keynes as egotistical because he was confident that most intellectual problems could be solved. I think this is a lame criticism. While he may have been arrogant, what is the big deal? Most of our Enlightenment-Era Founders shared this sentiment. The Austrian that we listened to last week sounded arrogant to me.
The author talked about Keynes changing opinions on the issue of freetrade during the 30's. While this could be a negative, I wonder if every situation needs a certain amount of flexibility with whatever your views are. Every economic situation is bleeding complex so it seems to me like you need to adapt to the situation. I can kind of see where Keynes was coming from when he said,"I am afraid of "principle." Why put yourself in a box?
This article did not mention Keynes views on the Versailles Treaty.I read in other sources that Keynes had the foresight to be against the large war reparations that the Allies wanted Germany to pay as a result of WWI. It is a fairly accepted view that the conditions created by the Versailles Treaty were part of why Hitler rose to power.
I found an insightful video that has Lord Skidelsky and Russ Roberts in it.