While I don't doubt many leftists were violent in those BLM protests, many of them were not leftists. Many were anarchists, which its hard to be both at the same time. Also, some who were actually charged by the federal DoJ were members of right-wing groups trying to ignite the race war. These aren't conspiracy theories, these are looking at the actual people charged with committing violence during these protests.

https://apnews.com/article/virus-outbreak-race-and-ethnicity...

https://www.justice.gov/usao-mn/pr/self-described-member-boo...

http://stmedia.startribune.com/documents/Hunter_complaint_af...