The political left has been campaigning against the use of force since at least the 18th century. So it is not surprising that they are now arguing that heavily armed or aggressive police forces only inflame protesters and thus provoke violence.
Statisticians have long warned that correlation is not causation, but they have apparently warned in vain.
There is no reason to doubt that heavily armed police in riot gear may be more likely to show up where outbreaks of violence are expected. But when violence then breaks out, does that prove that it was the appearance of the police that caused it?
I strongly suspect that people who travel with armed guards are more likely to be murdered than people who do not travel with armed guards. After all, they are not paying to have armed guards for no reason.
If so, should we conclude from a higher murder rate among people with armed guards that having armed guards increases your chances of getting murdered? Shall we also conclude from this that we the taxpayers should no longer pay to have Secret Service agents guarding our presidents?