If we had a justice system instead of a “just us” system, and if we had non-corrupt and non-lazy cops, there wouldn’t be vigilantes. But we don’t, so there are.
(3 good cops in my family, so I’m NOT anti-cop. I’m anti-bad-cop.)
IMHO a lot of cops got discouraged and cynical due to the last administration’s support of BLM etc, and disemboweling of state and local LE ability to actually do their jobs. And before that, rotten judges, the ACLU and all the rest. Pols and judges siding with criminals. Gotta be very discouraging.