That’s a lot of words to say “if you commit insurrection and storm the Capitol, don’t be surprised if you’re shot”Most likely they would be supporters of the castle doctrine for their private property, but also supporters of the first amendment.
Obviously they don't have a right to be in the public building in a restricted area just because they are using their free speech because the government is entitled to reasonable time, place and manner restrictions on speech.
Which its clearly reasonable to deny them access to the Capitol Building while in session and they can be trespassed by being removed from the premises - and that includes reasonable force.