Barkley Rosser and Brad DeLong say no, but it depends on definition and context. Barkley tries to talk his way out of it, but Keynes in the General Theory did advocate “a somewhat comprehensive socialisation of investment.” “somewhat” — that’s my kind of weasel word! In any case this was not the same as classical central planning circa 1920, but in a rap video I consider that acceptable license. By my count “central plan” comes up once in a ten-minute video and most importantly Keynes does not accept the characterization but rather responds that the debate is about spending. The video is not suggesting that each and every rapped point is true at face value, and if the two characters seem to debate past one another that too reflects the reality at the time.
Also consider another piece of evidence, namely the Keynes-approved preface to the German-language (uh-oh) edition of the General Theory:
Nevertheless the theory of output as a whole, which is what the following book purports to provide, is much more easily adapted to the conditions of a totalitarian state, than is the theory of the production and distribution of a given output produced under conditions of free competition and a large measure of laissez-faire.
Points in response are: a) Keynes does not seem to actually favor the German system, even if he thinks it is better suited to Keynesian doctrine, b) the Nazi system was not “central planning,” and c) this was written in 1936 before the worst acts of the Nazi state, planning or otherwise.
Nonetheless, in Keynes’s time enthusiasm for significant socialistic planning was common. Keynes had it too, at least for a while in the 1930s. It was a milder planning than the worst ideas circulating at the time, but it’s fair game to contrast it with the anti-planning sentiments of Hayek. Can you imagine Hayek writing a preface like that? I don’t think so.