However conflicting it may sound, arguments against freedom of speech and freedom of expression cannot be supported in an economic of free speech / expression. This is not actually a dilemma, because fascist politics are incompatible with these freedoms; one cannot exist when the other is the norm.
And just like in any culture and community, the best way to counter fascism is not incarceration and bans but heavy investment in high quality education, on the one hand, and heavy communal shaming and stigmatization of fascist politics and policies, on the other hand.