"Blocking someone from contracting you on social media isn't really a freedom of speech issue - so long as an alternatives means exists"
Kicking someone out of a town hall meeting is not a free speech issue, so long as alternative means exist. Kicking someone out of a public square is not a free speech issue, so long as alternative means exist.
The only difference in the Twitter case is that Twitter as a private company can freely exclude whomever it wants. The point is that a public official cannot direct Twitter to do so, which should include directing Twitter to block a particular user.
Kicking someone out of a town hall meeting is not a free speech issue, so long as alternative means exist. Kicking someone out of a public square is not a free speech issue, so long as alternative means exist.
The only difference in the Twitter case is that Twitter as a private company can freely exclude whomever it wants. The point is that a public official cannot direct Twitter to do so, which should include directing Twitter to block a particular user.