Not just visibility. The confidence that comes from solidarity. From infusing the passion of others in yourself. Watching the courage of the ones before is the kind of thing that inspired the leaders we have today. Not even just the passive ones.
To your second comment, how can a campaign to clean up so-called "violence in cities" continue to produce effective propaganda without the clips of violence or looting or property damage? Do you think the National Guard picking up trash in DC for nothing better to do or guardspeople sleeping on floors is effective?
The thing is, if there were outlets to report the people fighting back, throwing bricks against unprovoked police attacks, there would be a lot more to gain from violence. Unfortunately, there's virtually no outlet at this point that wouldn't write the narrative from Trump's lips in the case of violence against military/police regardless if it was warranted.