This comes down to a striking difference between what we might call "fashion" norms and "formality" norms that's often lost on people who don't naturally conform to either.
It's semi-widely understood that fashion norms are purposefully exclusionary, that changing routinely and unpredictably imposes ongoing costs that keep outgroups out.
"Formality" norms are not like this. They don't tend to change particularly quickly (though which norm is preferred in a given "context" can change if the context flip-flops), and they're not normally intended to be hard to "follow". They substitute for formal induction as a way to signal that, yes, while I don't actually know any of you, I share enough basic culture with you that we can reasonably expect to be communicating with other in ways that we both know how to deal with. (This is something you get to feel strongly when you try to work your way into doing business with people with whom you don't share enough basic culture to reasonably expect to be communicating on the same wavelength.)
And yes, some people do get left out that the rigors of the norm, but the alternative to having formality norms isn't that everyone is now willing to deal with everyone else. If people aren't openly advertising what social protocols they're ready to speak, you're still going to have to negotiate them once you get to the meeting, with substantial chance of failure. The alternative looks more like refusing to deal with people who you can't find someone you trust to vouch for, which, well, is indeed what tends to happen when trying to do business cross-culturally.