It’s the evolution of a social system guided by the same set of rules. There is actually a very good reason why social liberalism can’t make a comeback. The dynamic of liberalism that champions private ownership leads to capital accumulation in the hands of the small capital owning minority. As the system continues to function you hit a point where the oligarchs have disproportionate power in society leading to the transition into neoliberalism that we’re living under now.
Social Liberalism came about as a response to Classical Liberalism creating the same oligarchic problem you just described.
If it happened once, it could happen again.
I don’t know if it will, but its certainly possible.
Things don’t just happen randomly, systems evolve according to the rules society agrees on. In order for things to change, an iconoclasm has to happen first. Then a new set of rules will be created, and that will no longer be liberalism because that’s the ideology that will be cast aside in the process.
You keep saying Liberalism as if its only one thing. I’ve already mentioned three economic philosophies, each creating their own new set of rules. I’m honestly not sure we’re talking about the same thing.