Most large companies (especially in regulated industries) have strict social media policies, e.g. preventing employees from performing company business via their personal social media accounts, with penalties for serious breaches being disciplinary action up to and including dismissal, i.e. it is possible to separate company business from non-company business. Why not the same for those working in the political sphere?
Businesses fear liability. Governments should be built on it.
Taking twitter away from congressmen won't stop superpatriotsforbaldeagles.ru from distributing political propaganda, or random people being fed extreme media each inside their bubble.
The issue is inflammatory content spreading like wildfire, and direct intervention from politicians themselves is just tiny drop in the ocean.
What does this actually mean? Are you trying to ask politicians not to engage in politics? News organisations? Billionaires? Foreign intelligence services? Asking for legal restrictions on who's allowed to speak about what?
And to clarify, this is actually a really important question because it predicates the entire discourse of separating social media and networks from politics.