Earlier quoted context omitted.
- Social media should not allow the broadcasting of unproven allegations that individuals have committed crimes, just as conventional media is barred from doing so until the cases have been heard in court. - Utility-like services should not be allowed to refuse service to individuals without clear reason.
#1 seems practically impossible to do, considering that the definition of what a crime is tends to vary between jurisdictions. It may work if on a closed internet and social media that is segregated by jurisdiction. #2 is already true in some cases, but as usual, the real answer is something like "it depends."
Alleging that someone has done something that happens to be a crime aren't a problem, the problem is wilfully alleging crimes outside the court system. The overwhelming majority of the posts that cause these problems either explicitly claim that someone has committed a crime, or explicitly claim that someone has committed an act that is well known to be a crime.
> #2 is already true in some cases
Not really in the US AFAICS? Certain narrowly defined groups are protected against being denied service by private businesses, but there's no broad general protection.