It did more than that. Our country was already well down the road to socialism due to the policies of LBJ's hero, FDR. However, LBJ did accelerate that effort with Medicare, the Voters Rights Act, and other things.
Many in the South thought LBJ would be a conservative since he was from Texas, but he quickly dispelled that idea. He did it mostly for his own self-agrandizement and to further the future of the Democrat Party by solidifying the black vote behind them. (I also think he had the hots for Jackie and wanted to prove to the snooty Kennedy liberals that he was not the country bumpkin they made him out to be. He was saying that he was one of them, a liberal.) That moved the Democrat Party firmly into the Liberal column where it had previously been rather conservative due to the many Southern politicians with seniority and key positions in both houses of Congress. Many misguided Southerners worshipped FDR because of his welfare programs during the depression. Otherwise, they were conservative.
It was clear that the other big Republican guns in 1964 (all moderate Governors), Nelson Rockefeller of New York, Bill Scranton of Pennsylvania, and George Romney of Michigan, had little interest in supporting Barry Goldwater.
1964 also marked the beginning of the decline of the "Country Club Republicans" from the NE and the rise of conservatives in the Republican Party. Goldwater didn't win but his ideas had a lasting influence. Reagan was a direct result of what happened in 1964, so yes, it was a pivotal year.
“It did more than that. Our country was already well down the road to socialism due to the policies of LBJ’s hero, FDR. However, LBJ did accelerate that effort with Medicare, the Voters Rights Act, and other things.”
And Nixon not only failed to repeal any of Johnson’s programs, he added more. Which is one reason that Republican moderates are a bad option.