Say you're deciding between two programs (or AI models)[0], you prefer an open source one, a colleague prefers one that just pretends to be open. You say your choice is preferable because it's open, he says the same about his choice. Then you say the dreaded "well, actually" and either you sound like a fundamentalist or an asshole.
[0]: None of those are truly open source because they're all trained on stolen data. And see? Now I sound like a fundamentalist.