It's bunkum.
Also, once I realised that my awful neck and shoulder pains were actually a symptom of my migraine and not the cause, it changed a LOT!
Keep a record of your migraines, how long they last and how they present etc. Speak to the GP about whether you are at a point of looking at preventative medication alongside triptans to stop the attacks.
Getting a good meds regime is all that worked for me. I've spent thousands and thousands on chiropractors, osteopaths, sports massage, Chinese massage, western medicine acupuncture, Chinese acupuncture, every gadget that goes viral, ice helmets (really help me!), a Cefaly (expensive, didn't make much odds), every recommended vitamin regime, exclusion diets, FODMAP, anti inflammatory diet, both daith pierced, pressure points, blah blah blah.
After 25yrs I'm under neurology and having CGRP injections which is all that has worked in that time and is a game changer for me.
Oh and the neck and shoulder pain vanished when I had Botox (the full protocol) with extra injections in that region. Absolutely brilliant.