A debate about open debate
nytimes.com
nytimes.com
When you can get almost every giant multinational corporation to repeat your message and give huge donations to your cause, and when the supposedly most racist president in recent US history was barely able (or just wasn't willing) to make a dent in immigration numbers, do you really have "little political power"?
The thing is that the US has a long history of ordinary liberal democracy coexisting with white supremacy. Not just in opinions but in actual reality - Jim Crow was the law in a large minority of the country 'till the 1960s in significant minority of the country. This situation looms large in efforts to deny a platform to white supremacy.
"Should we allow free speech for white supremacists" has been a constant question of civic class but with the tacit and generally disingenuous implication that none of the people in such effete debates would ever subscribe to such things but that this is what happens in an "oh-so-wide-open-and-tolerant" society as the US. When the reality was loud speech favoring white supremacy been just below the surface in a fair portion of American society.
Consider how Charles Murray's soft racist positions get a wide display at US college financed by a large network of right wing racists. Charles Murray has appeared in large university ballrooms, not because of academic credentials but because of money - protests by the student and faculty have periodically forced this racist to retreat.
That's the fight to allow or deny people platforms has been going on as long as platforms exist. Not every fight the left or right engages in hear is reasonable. But the fight deplatform misogynists and racists in particularly from socially significant platforms seems good and the push back seems disingenuous. "Free speech for anyone, even Nazis" is frequently "free speech for the pure mainstream and for Nazis but no one else" - remember Milo Yiannopoulos.