“Reagan conservatism” is simply an initial stage of neoliberalism. It inevitably leads to moral collapse in its subsequent stages. I’m sure Reagan himself didn’t anticipate that but not thinking through the consequences of your actions is not conservative.
Since the times of Reagan and Thatcher, neoliberalism has been embraced passionately and excitedly by the Left. (See Leftism Reinvented by the leftist professor Stephanie Mudge). Neoliberalism, with its emphasis on constant change, is natural to the Left and unnatural for conservatism. The reason why we can’t go back to Reagan conservatism is that it’s impossible to replay the initial stage of a process that moved on and mutated. You can’t stuff a butterfly back into her cocoon. Competing with the Left on the field of neoliberalism is a losing game.