Seeing as the rest is just useless drivel, let's just keep this part and go with it.
Yes, it is covered under the first amendment. Context is important here, so try to stay with me.
Trump has already made official statements live from his personal twitter account. Official statements can only come from official sources, so even if it is a private company that owns the website where the statement is made, that is an official source of information. (Hence why Spicer confirming that he is indeed making the statements as official is important - If he didn't, there'd be no reason to think they're official other than "Some liberal said so." The White House has confirmed Trump's personal twitter account is being used to make official statements, meaning his personal twitter account is an official source of information.)
If official statements are then being withheld from it's citizens, that is in direct violation of the first amendment, which exists to prevent the government from "interfering with the distribution of information and opinions." Withholding information from it's citizens is by and large EXACTLY that - Interfering with the distribution of information.
It's pretty black and white. And before you go calling me a libtard, if Obama blocked people on the official POTUS twitter, they'd have had the exact same right to go after him. If they didn't, that's their own issue - Although the only thing I can find on it is
http://calconservatives.com/fact-che...ic-on-twitter/ which clearly seems to say it was completely fake and makes no mention of the original screengrab. If you'd like to provide a source on that, feel free.