A core problem with contemporary leftism as it is often pursued is that it has no sense of the boundaries of its project. Casting it in the most reasonable light, it tends to make the entire world and every person's soul its political mission. After correctly identifying thought systems that lead to undesirable consequences, leftists often try to frame their activism in terms of "abolishing patriarchy" or "ending racism". Because they believe these thought systems are at the root of the problem, it is natural to assume an attitude of attacking them.
Much like wars on victimless crimes, these attacks must be directed at people, since the ideas only exist in the mind. Individual human beings are often rejected in totality rather than merely rejecting their bad ideas. After all, individuals are sovereign within their own minds, and there is little power to force the adoption of values onto another (setting aside the countless problems with using force). The only real non-violent sanction one has against the beliefs of another is ridicule and withdrawal, which the left certainly employs often.
The question the alternative left poses to the mainstream and/or orthodox left is not whether these strategies are just - certainly, the defense of free association is a vital liberal tactic for non-violent social discipline. Sacrificing free association utterly endangers liberalism. Rather, its critique centers around the effectiveness of the tactic. Rather than a universal application of leftist ideology to every aspect of life, a lighter touch is suggested - not to let bad ideas and practices off the hook, but to better inculcate values conducive to sustainable social progress.
By its very nature, political activism orients itself towards formal institutions. Success in politics is measured by power - the power to realize visible and articulable policies, the power to direct the apparatus of an institution or organization, the power to compel individual behavior. Politics is practiced in spite of individual prerogative through capturing and dominating institutional vehicles for social influence. Certainly values can attempt to be promoted through these institutions, but ultimately they are the application of mechanistic policy or law to effect observable phenomena or measurable behavior.
Resisting or promoting particular institutions are valid forms of political activism because there's something to resist or promote. For example, racist institutions - institutions that realize ends deemed racist - can be reformed or abolished. Unjust laws can be stricken and undermined. Organizations with objectionable values and goals can be disbanded or delegitimatized. Activists can target institutions with precision because they are easily identified entities with tangible assets, finite memberships, and/or express governing rules.
But the values that impel individuals to organize in the first place are not so easily eradicated. You can prevent the Ku Klux Klan from meeting and its members from acting, but you cannot force each member to renounce racial supremacist ideas. The Nazi party, its tenets, and its insignia are positively banned by law in Germany, and yet that poisonous belief system still lingers in the minds of many Germans. In fact, the attempt to stamp out such individuals for their beliefs can often create blowback: by marginalizing individuals for their beliefs, they become that much more dedicated to seeing them realized. They can come to identify with their ideology much more completely if their own well being is threatened.
How do people shed old belief configurations that are tied to their sense of who they are and adopt new ones? After all, lasting social and cultural change occurs through changing the behavior of the society's or culture's constituent members. And behavior follows from a person's sense of their values and self-interest. So the key to long-term, lasting social progress of the kind we want is not political at all - it is changing minds and hearts.
People who are willing to be pariahs for their unpopular beliefs are unlikely to be cowed by ratcheting up hostilities. One can see this in military occupations where soldiers of one culture attempt to force those of another culture to change. One can also see this in movements here that embrace backwards approaches yet linger decade after decade, changing only in their application of beliefs and rarely in the bigotry motivating them.
Few people adopt their basic values on a rational basis. These values and beliefs are the basic "axioms" that inform their further reasoning, but the examination of these axioms usually reveals that some emotional or unconscious dynamic at play. Even the liberal belief in egalitarianism and justice is not one "supported" by any objective data; rather, we accept them as givens and use reason to find the best ways to achieve consonant goals.
In order to change one's values, one must face the emotions, experiences and psychological background that convinced one to adopt them. I'm suggesting this is a deeply personal experience that requires a facing of the self, a "dark night of the soul". It requires a vulnerability and honesty that is not well suited to the political project of influencing institutions and debating policy. We are asking people to dissolve basic parts of who they think they are and adopt new ones that are alien. This is a big step for anybody, and many go their whole lives without engaging in such a self-examination.
If our real desire is to convince people to substantively abandon bigoted and undesirable beliefs and values, and not simply eliminate the superficial vehicles informed by them, we must help people, not compel them. Decent societies are comprised of decent individuals, and if we rule out eliminating people for their beliefs then we have no choice but to work with them. This is a long, hard path that requires a dedicated ministering to deeply angry, hurt, or insecure people. It will also challenge our own beliefs and require honesty and transparency on our own part.
Building genuine trust among suspicious parties requires a light touch and a long view. But this is how a voluntary society and enlightened culture is created: individual by individual. The coarse means of political activism can stop large scale tragedies, but it cannot prevent them over the long run. To do that, we need to focus on being our better selves and bringing out the better selves of our neighbors. This scale of activity feels totally unequal to the task, and for precisely that reason it is too often ignored in favor of political activism. But while it feels unequal, it is the only viable route to sustainable, long-term social and cultural change.