Obsession about anything can drive one over the edge.
It’s like stalking but not a living person but a thing or topic or lifestyle.
The left has found the QAnon cult helpful. If you don’t think your child really should have a Covid vaccine or if you are sure the Democrats cheated and gamed the system in the 2020 election, you are put in the same category as the QAnon Shaman.
The QAnon stuff kept a lot of people busy following a rabbit trail of conspiracy theories rather than doing mundane things like getting out the vote for conservatives. And it discouraged voting because “the conspiracy” controls the votes, there is nothing you can do about it, so stay home and let the socialists win.
IF I were a Russian or Chinese operative, I would consider QAnon, and BLM, Antifa, etc. as all being convenient tools in my toolkit for undermining America. But there isn’t quite an equivalence. QAnon followers might have been involved in one riot. BLM, etc. are behind 500 riots. But it’s all bad.