Personal anecdote and not a doctor, but mine went away, or rather is managed, with weight loss assisted with GLP-1.
In retrospect I wasn't being honest with myself in regards to how much I was eating or the quality of said food.
When I first started GLP-1, my appetite (really cravings) mostly went away and junk food beyond a tiny handful made me incredibility sick with flu-like symptoms.
Now that I'm at my goal weight, still taking a maintenance dose of GLP-1, I can cheat a bit more without side effects, but a burger and fries or a pizza will absolutely trigger my IBS to this day if the meal is over ~500 calories.
Eating clean and not overindulging has caused the opposite problem. I have to supplement fiber or I won't poop for a week. Its not uncomfortable constipation either, there just isn't a lot of waste there to eliminate.
Good luck on your pooping journey!
edit: Also seconding a bidet!