I am not a free speech extremist, and recognise you need to balance the competing demands as these platforms are defacto digital town squares. There are several problems that currently exist. They are:
1) Who decides what is and isn't on the platform Now that the web has effectively been centralised into a handful of organisations, being locked out of a platform can be seriously harmful. There are no appeals, or arbitration on decisions made. No courts to provide an independent check.
2) Asymmetry of rule application The biggest issue is rules are not applied fairly. Certain types of people seem free to repeatedly break the rules on platforms without recourse.