Its open v closed society. Liberal v Authoritarian.
The very definition of liberal has been hijacked and distorted in various ways. Today when someone says liberal, what they actually mean is neo-liberal economics (aka economic libertarianism) rather than liberal values of equality which are best summed up in the US Constitution:
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the Pursuit of Happiness. That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed
What we are seeing is the idea that all people are not equal. Identity politics rather than aiding equality, has lost sight of the point about equality being about the most vunerable in a situation regardless of their identity.
Identity politics is much more of a hijacking of the ideals of liberalism by twisting and exploiting them for gain in order to produce inequality and to gain power.
The problem is really that people who are comfortable and don't understand the underlying principles of rights and why there was a need for them, don't really understand why they worked. Its complaceny.
Liberalism exists BOTH on the left AND right, and neither has done a great job of educating people as to the value and principles enshrined within it. Instead, the economic temptation of neo-liberalism has proved to hard to resist and very much unmined the balance of power, leading to exploitation and abandonment of those principles of all people being equal and worthy of respect.
With that context, those who are being exploited no longer feel that the contract of democracy, in which power is given to government by consent of the population, is working for them so look for alternatives. Of course this dis-satisfaction is also being exploited within this by authoritarians, but people do not yet feel the betrayal they have felt from those who profess to support liberalism. Its too early in the cycle, and the promise of a better future is very much still on the table. Hope is something which is incredibly difficult to crush within the human spirit.
This won't dissolve until authoritarianism has shown its ugly side - destroying that hope, or liberalism has managed to get rid of that cynicism and can offer a better alternative in which something better is on the table.
Arguably, it has already reached a point whereby liberalism can not defend itself, without the ugliness first showing itself in all its horror.
I certainly don't think this the fault alone of the left. Both the left and right have failed, through their own shortsightedness.
And its certainly not too late to start get back to the basics of why rights exist and what they protect us from, rather than simply parrot like stating that feminism is about equality of the sexes (its not). Unless you have the undertstanding behind the principle it can (and is) be used maliciously against that.
Indeed with the rise of authoritarism, it most definitely is the time to getting back in touch with those foundation stones and to learn lessons from them in order to limit the extent of the ugliness.