Because people don't grasp what "free speech" means, at least in the US context.
Freedom of speech (expression) protects one against government interference with expression. The US government can't stop you from saying bigoted, racist, or sexist things because you have the freedom to express yourself.
But.
Freedom of speech doesn't require anyone to offer you a platform to share your views, nor does it mandate an audience. If your views are unpopular, freedom of speech doesn't prevent others from denying you business or employment generally either; the ol' "consequences of your actions" principle.
Bad actors want the right, a mandated platform, and no consequences for being shitty. They get upset when they find out that they're entitled to neither a platform nor protection from consequence.