Now nobody trusts the Democrats. They're lucky to have such an incompetent president in office in Trump, and they'll likely win in 2020 regardless of who runs based on that alone. But if an establishment Democrat wins, someone like Trump, if not worse, will arise in 2024/2028 and just restart the cycle because they won't significantly change any of the reasons that led to Trump ascending to the presidency, just like Obama didn't actually fix the issues that led to the financial collapse in 08, or NSA domestic spying, or the drone program, or campaign finance reform, or raise wages, etc.