Considerations of protests / protesting is subjective.
There was a fair amount of folks that felt highly disrespected.
What was offensive were the laws at the time.
But what Rosa Parks did was directly connected to what she wanted. She wanted to be able to sit where she wanted on the bus, so she did.
She didn't say "I'm going to disrespect this symbol that you value, until you let me sit on the bus". Some people were offended, of course, but there's a fundamental difference here.
Rosa Parks was acting
against segregation, she was saying we should all be able to sit where we want regardless of skin color.
The anthem protesters are saying "We can't respect your country because it oppresses us". That's acting in an exactly opposite way that Rosa Parks was. They are separating themselves instead of acting to unify. Rosa Parks was trying to erase the differences that separated us.
Again, I have no problem with the idea that they want to protest, but I think the manner they have chosen to do it is a mistake.