The higher power portion of 12-step programs is not documented to be effective (and I think in the 21st century there are studies to show that effect.)

When someone only has access to 12-step programs for support, I point out they can still be useful given they work like a shotgun, using a scattered array of methods. You might still find a sponsor, or check in weekly, and find affirmations that help. Also, there might be snacks.

Even if you declare yourself openly atheist and disregarding the higher-power steps, the constraints on cross-talk should limit criticism of that. Granted, group meetings are subject to people being jerks. And prisons are rife with abuse of power, of which religious coercion is one kind.

It is impossible to follow step 11 in a secular way without totally rewriting it:

11. Sought through prayer and meditation to improve our conscious contact with God as we understood Him, praying only for knowledge of His will for us and the power to carry that out.