That's not anecdotal, there was an actual peer-reviewed study published around 2024 or 2025 on this. Seen it referenced on here plenty of times. Maybe someone else still has the link handy.
Don't have time to dig it up myself, but it is documented that abdominal side effects tend to run higher for some people. More side effects doesn't automatically mean more effectiveness though. Like you said yourself, what you went through didn't end up benefiting you.
If the kwik pen is an option, starting below 2.5 might actually help. My mom did best starting around 1mg, since she lacks insurance I mix her tirz from a compounded vial myself.
Some people just don't tolerate certain meds, that's real. There are ways to ease side effects too, things like Zofran, digestive enzymes, adjusting how you eat. Sounds like another attempt isn't in the cards for you though. Sorry it didn't pan out, but Mounjaro's been a game changer for my fasting insulin, blood sugar, A1C, and other inflammation markers.