That is an interesting point of contention. I'd say that both sides are actually quite even in their weaknesses and strengths.
I'd have said the post WWII team was a bit stronger in batting. Amongst batsmen from each era you'd have Hobbs, Hendren and Woolley against Hutton, Washbrook, Edrich and Compton, so I'd say that the latter is a little stronger.
As far as bowling goes both sides were extremely weak. As far as the most successful bowlers you had Fender and Parkin who took fewer wickets but at a better average than Bedser and Wright.
Both sides had very similar records, going 0-5, 0-3, 1-4 and 1-0 after WWI and 0-3, 0-4, 1-4 and 1-0 after WWII. Both third series were dominated by one English bowler (Tate and Bedser) with another (Kilner and Brown) in distant support, while the earlier series had two performing batsmen vs one for the later.
And both teams had lost their potential best bowlers during the war, with Farnes being killed and Foster's motorcycle accident ending his career.
It's an interesting one, and I certainly wouldn't describe one as being markedly weaker than the other.