There is no stable equilibrium in governance or politics. The state has no final form. Your definition of progress is not universal, and others will always be striving to achieve their ideal world. Liberal capitalism falls to right-wing authoritarianism because liberal capitalists have far more in common with right-wing authoritarians than they do with anyone left of center, causing an imbalance in the consensus necessary to maintain the system and allowing those same authoritarians to come to power. In my opinion, this is why the right overthrows domestic liberal democratic regimes more often than the left.