I agree with this author’s point but what is missing is that liberalism’s history is one of abject failure. See the War on Poverty, Obamacare, communism, Venezuela! The Public School system! How many failures and disasters does it take for people to realize that liberalism leads to failure wherever and whenever it is tried.
The problem is, the children are not being taught about all this abject failure. So no matter how badly leftism has failed in the past, it always gets a clean slate with the next generation.