More of a poke at the British for still using fixed pitch props at this time
Fokker was developing new models but how far removed from the D XXI is certainly subject to question.
The XXI was certainly not a bad plane in 1936. However by 1938-39 it was certainly no longer 1st rate. It might have worked against the Ki 27 or the A5M but as soon as any opponent shows up with a retracting landing gear fighter and a decent two row radial the XXI is in trouble, such was the rate of aviation progress back then.