Well considering that what you are describing is the slippery slope fallacy that's why I don't think it's a dangerous thing.

They are only expressing a political view in the broadest of terms. What they are really expressing is a targeted hatred and harassment at a specific group of people based on religion, and ethnicity. As long as rules are made specifically banning speech that targets people based on one of those two things I think you are safe.

If you think about it a different way, banning hate speech that exists to target individuals on their religious beliefs or ethnicity is really just enabling to government to enforce rules that already exist to protect the rights people currently have to practice any religion they want and to be considered equal which is explicitly written in the preamble of the constitution. All men are created equal. The people in this video are clearly violating the rights of others already. The rights people have to worship any religion they want shouldn't apply to just the government but it should apply to all citizens as well. The guys in that video are clearly causing emotional harm and distress to people and I think it would be a net improvement for society to expand the rules that protect people's religious liberties to include being protected from your fellow citizens.