Hitler also expressed token opposition to leftism. But this does not change the fact that he considered himself a socialist and proceeded to de facto nationalise huge swathes of the German economy.
Back to Nixon, his economic record is crystal clear. I'd argue that his economic policies were almost as statist as Johnson's. He got rid of the gold standard, supported the creation of the regulatory state, strongly pushed Congress, and worked with Ted Kennedy, to try to create a national health service, enacted economy-wide price controls and has the worst record on domestic spending out of any President since Eisenhower. Non-defense, non-interest spending increased by a whopping 73% during his tenure - on average, an expansion of 9.9% per year. Even Obama admitted that Nixon was further left than him.