It was the same thing with IE back in ancient times. A popular browser violates web standards so many sites were designed with that rogue browser in mind. If you use a browser that actually follows the standards, some sites just won’t work properly for you.
In summary: You and me, we’re in the same tribe, and we hold the superior worldview. Those people over there in the out-group are wrong. They also do things the wrong way, because they aren’t in our tribe.
Hearing this sort of talk pulls some strings in the human mind. There’s this interesting default setting that says tribalism = TRUE.