Somewhere along the way-- beginning long, long ago and continuing into the present day-- most humans got the bizarre notion that things which could never possibly be any of their business, were their business.
And not only that, but so critically "their business" that they should murder people over these things.
Which invisible beings they believed in, and how they showed their belief.
Which things they ingested.
Who they loved and/or had sex with.
How they comprised their family units.
Which tools they owned, and how they carried them.
What they lived in, and what they surrounded their living quarters with.
What they traded, and how.
Where they were born, and what languages they spoke.
Which banners they flew.
Which symbols they revered.
Which songs they sang.
And all manner of other things.
I'm not even saying these things don't matter, but that they should be individual matters. Not subject to control by anyone else, and certainly not justification for murder!
All they should have been worried about the whole time was whether the other people initiated force or violated property or broke their agreements. But that was too sensible, and didn't allow for the rise of a bully class (who tried to make the non-issues become Big Issues).
It's really long past time for the human race to grow up and get over the childish desire to meddle and control. And we can- one individual at a time.