When we bemoan the creation of free-speech zones around conventions, conferences, summits, etc I think it important to remember whose actions made those zones necessary in order to protect the right of free assembly.
Prior to 1968, such precautions never occurred to anyone, because the culture of the time abhorred the idea of actually attacking someone engaged in political activity. For the narcissistic lefty boomers, that wasn’t good enough. As individuals gifted with intellects and morals far beyond those of mortal men, they had the inherent right to impose their will on others by force. Ever since then their intellectual progeny have attacked every major political event in the North America.
Viktor Frankl observed that freedom resulted from the combination of liberty and responsibility. He we see he was correct. People once had the freedom to protest close to conventions and similar gatherings because they behaved responsibly when doing so and protected the rights of others. After leftist extremists developed an utter disdain for the rights of others, they abandoned any concept of responsibility towards others.
And here we are. This is how freedoms die, not with the loss of liberty but first with the loss of responsibility.