I do find it hilarious that the Leavers who are like 'I'm so glad we left the undemocratic EU!' and shouting at those who are upset at the result for 'not accepting democracy' are adamant that these kinds of marches or people airing their opinions about the fears they have going forward shouldn't be happening

funny that, isn't it?
I accept the democratic result. Do I agree with it? No. Is it mine and other people's right to speak out in favour of the EU and air our concerns about the result going forward? Yes. That's democracy. It works both ways.