I thought one interesting point was on healthcare. For rightwing economists the mistake was:
There is already considerable health care cost control embedded in the ACA, most of all for Medicare, and this is not admitted with sufficient frequency.
For left-wing economists the issue was:
Use of a strong moral argument for universal health care coverage, combined with a fairly practical, hard-headed approach to the scope of the mandate, and not realizing the tension between the two. Failure to indicate where the "bleeding heart" argument actually should stop and at what margins we should (and will) let non-elderly people die, if only stochastically.
In other words right winger ignore the cost controls in the ACA, but left winger refuse to admit that it will mean more and better care for many but poorer care for some others, even to the point of death. This was the point of the overheated discussion about “death panels”.