I suspect that is the right answer. Prior to Dunkirk Hitler was ruthless in his conquest of Europe. He made a very bad error. Those troops on the beaches of Dunkirk some years later carried the spears that defeated Hitler along with the rest of the Allied Troops.
On the other hand, if Hitler could have gotten a deal with Britain (he probably thought Churchill was finished), it would have freed up a lot of troops for Operation Barbarossa. There probably wouldn’t have been the campaign in North Africa and manning the Atlantic Wall in France would have required a lot less manpower.