I think it’s less veganism and more how noisy and evangelical the loudest vegans are.
If you’d just said veganism, I’d agree, but you went on to emphatically tell us all the reasons why veganism is better. All legit, sure, but all the underlining gives it a particularly condescending tone. It’s not veganism that irritates me, it’s how condescending so many vegans become. Same camp as CrossFit for me. They’re both cultures I don’t really care to be a part of.