You could compare it to Windows vs. Linux in a sense. 3ds Max has decades of legacy plugin/SDK compatibility baggage, lots of commercial and contractual obligations with business/enterprise customers... and Blender has none of those things weighing it down.
Well, I have been using 3DsMax and Blender from the early versions and it's always been the case that Blender is way faster.
Legacy baggage has nothing to do with it, in my opinion.