I've been on the basic FODMAPS precursor since the late 1980s, before I became chronic, for food chemical sensitivity reasons. Made a huge difference to my life, health and sanity. Once you get used to recognising the food groups, you have stacks of freedom.
My niece and also a young cousin needed to go on FODMAPS soon after it was first published in this format. Again, totally changed their lives and health status, resolving PCOS, digestive and some headache issues. I don't know how my cousin is now. I know that since my niece had her first child and breastfed her, she hasn't needed to return to this level of dietary discipline.
Good luck!