The problem is that then the people are never heard. I used to think this way too but they have a point, if they aren't literally in your face, you're going to walk right past them. We've all seen people on the sidewalk handing out flyers trying to get the word out - how many of us stop to read it? <10%? <1%?
It's a no win scenario no matter what, that's what I mean. If they get in your face people don't like them and we get these arguments. If they protest over there in the protest spot they get ignored. If no one protests then nothing gets done. There are no valid options. I don't like it, but I don't blame them either for being frustrated that no one cares
You don’t need to take and read their flyer to get the message… I can agree with their message, and still be pissed off that they’re causing a disruption in my day. These kinds of people only hurt the cause.
If you're not actively involved in a movement your thoughts on the effectiveness of it are relevant because you're one of the people it is trying to affect.
You're maybe one of the people they're trying to reach. If so, thoughts along the lines of "I don't like this behavior" might be helpful for the people working to strategize in the movement. Responding to a protest with "I don't think this will be effective in convincing people" says one of a few things:
"I agree with some of the goals of the movement on the surface, but I would rather start a conversation about civility than about the actual problems they're trying to bring attention to"
"I disagree with their goals and I would rather shift the conversation to be about civility than to have to defend my position"
"I'm apathetic to their goals and I don't like being inconvenienced, so all I care about is how civil they are being"
Every one of these is an attempt to derail the conversation due to emotions ranging from discomfort to malice, and none of them are worth engaging in.