If Moscow would have been the focal point from the beginning it might have turned out differently.
The question is, what would it have taken for Stalin to be overthrown? Some suggest that may very well have been in the works, perhaps with Khrushchev as ring leader.
That is probably one of the greatest what-ifs in that war. Hitler’s focus on a huge front in Russia destroyed their ability to focus forces and make a breakthrough.
The second worst was allowing the SS into the areas they had conquered. The SS actions mobilized allies into enemies and created partisans behind the lines.
Moscow would had turned into Stalingrad, if Hitler had focused his armies on Moscow instead. The Nazis were not prepared for the Russian winter so they would had lost momentum by the time they’ve reached Moscow.
I disagree: if he had gone for and sized the oil fields first. That would have shut the Russians down.