No absolutist ideology can allow criticism and survive. Be it communism or some form of theistic belief; because there's really nothing there. That's why the enlightenment (1700s) happened after the scientific revolution (1600s), and not the other way around. But I think the internet will do what the printing press did in Europe.
As far as liberals are concerned, I'm a 1960 type of liberal. That is far left. We doubted any form of authoritarianism. So I can't understand today's watered-down version. Tolerance in our day never applied to things like any form of repressive religion.
Islam would have been thought of as some effort to "put us down" as we would have said.