However you read the constitution it's not the way courts interpret constitution now. Unitary executive branch doesn't exist for last ~135 years, and was under scrutiny before that (and with way smaller federal government).

With current supreme court nothing is sacred for sure, but overturning this and granting universal executive power into hands of president would be a disaster leading towards either authocracy or revolution. And yeah - that's all very similar to how fascism started, whether you would like to see it or not.