Not solely due to Hitler's leadership choices, but it certainly played a factor.

One of the reasons why Germany focused on Super-Weapons was the recognition by those in the armament industries that Germany could not even hope to out-produce or even come close to matching what the Allies were producing in terms of aircraft, armor etc. It therefore adopted a "quality over quantity" stance in the hope that superior units could overcome more numerous foes.

With that said Hitler was a firm supporter of the numerous Wunderwaffe and the more famous Vergeltungswaffen (V-Weapons, the V-1 and V-2 rockets). However, as Reich Minister of Armaments and War Production Albert Speer noted in his memoirs, Hitler only approved Wonder Weapons if they were of an offensive nature. The example you have given, the ME 262, was originally supposed to be an interceptor, was switched to being a ground attack/light bomber on Hitler insistence. This delay prevented it's mass production until Hitler finally gave way in 1944 and it was reverted back to being an interceptor, but by then it was too late to make any decisive impact.

So to answer to your question, no, Hitler's leadership was not the sole reason German armaments switched from Mass production to Wonder Weapons but it could not have happened with out his approval, though as aforementioned this lead to problems in development between what he wanted and what was best for the Reich at that stage of the war

(Sources: Joachim Fest Speer: The Final Verdict)