I see this a bit differently and will provide an example of how I view these protests which I think is more accurate.
Let's say there is a 2nd amendment protest scheduled. I support the 2nd amendment. I want to go to this rally. The point of the rally is to specifically voice discontent with State policy regarding an upcoming bill before the state.
First, I learn they are holding the rally on a campus. (I would ask the founders why it's not at the capital). Next I find out a lot of students are planning on joining. (This would seem odd to me as 2nd amendment rights don't tend to be popular among college students, so I'd ask why)
Then I find out these students are primarily fraternity folks. Hmmm.. well...
As the protest starts the plan changes from a protest to deciding to take over a building on campus.
Beyond that, the "college students from fraternities joining" are Proud Boy folks.
If I elected to STILL attend said rally (which I absolutely wouldn't and would actually be against, for the record) I could, hypothetically argue I'm not a racist, and I'm just here because I support the 2nd amendment. However, my attendance is likely going to get me labeled a racist, criminal and idiot.
Rightfully so, even though I don't specifically support those, I'm showing up and being a part of a rally that commits criminal acts and DOES support them.
Granted, I could argue the rally got co-opted, but if I knew before or saw during any of these developments, then the resulting issues regarding my reputation are entirely on me and fully deserved.
Oh, and nobody even knows or is aware of the bill that I was against to start with regarding the 2nd amendment. Nobody is even talking about it. They are talking about the Proud Boys and their criminal activities, with which I'm now associated.
That's on me.