That’s backwards. Society does not move forward despite free speech, rather because of it. The only way to truly move past harmful ideas and ideologies is to show those who would otherwise subscribe how dumb they are. You can try to quell them, but that just lends to their appeal, and results in those that do subscribe being more extreme and doing more extreme things. For a real world example, take someone who thinks that Nick Fuentes is a reasonable, respectable guy, and then show them the recent discussion between him and Hunter Biden, and see if they don’t at least get uncomfortable, unsure.
If this were true, far right mainstream media (eg Newsmax, NY Post) would not have the viewership and readership they enjoy.
In any case, few people here (and in general, IME) are suggesting that Nazis should have no platform whatsoever, only that we shouldn't choose to associate ourselves with those platforms -- especially when there are so many perfectly viable alternatives that don't occasionally promote Nazis to your readers.