That’s the thing. Chiropractic could be considered a manual treatment which is a therapeutic modality. PTs do manual therapies that are less traumatic and are one component of the musculoskeletal issues that contribute to pain that chiro claims to heal. For most situations of acute back pain they resolve in 4 to 6 weeks so even the ineffective treatments appear to help- it’s just like treatments for the common cold.
I mean if it is a bell curve, even an average person is smarter than half the world. There’s a selection bias on social media because those heated and ignorant threads get memed and shared either by people who believe the nonsense or by outrage.