Free speech absolutists believe that any limitation on political speech is veering into dangerous territory.
They believe that restricting free speech in any way, including curbing insulting or factually incorrect speech, means assigning gatekeepers who decide what can and cannot be expressed in public.
This process is littered with hazards – it’s ripe for abuse, there’s no clear consensus on who would be qualified to determine this
Limits to free speech should be limited. Only speech used in pursuance of another crime – threats, incitement to panic, incitement to crime, corruption, bribery, etc., should qualify as "illegal" forms of speech, not because of the speech itself, but because of the illegal consequences and intentions (mens rea in Latin) of the speech.