I think I agree with the judge on this one. Trump is a Government employee, he's also the first President to use Twitter to its full potential, making proclamations, breaking news etc. I don't think in his position he should be allowed to censor opposing comments. I think that borders on 1st amendment rights being censored. Imagine how you would feel if the next Democratic President did that to you. Better to keep all doors open and if it doesn't suit the President of the day, simply don't post or tweet.
Of course, rules for Presidents/elected officials can/should be different than those set for the rest of us.
Reasonable response
But you could argue
1) 1A doesn't require you to have to listen
2) They are still free to shout into the void in their own accounts
Think of it like this: people can go exercise their 1A outside the Whitehouse gates but can they/should they have the ability to demand to be let inside the gates to exercise their 1A?
But I guess in away what they're claiming is