Moving the discussion here so that we don’t derail.
I think the “generally” may be a bit of an overstatement. I definitely accidentally swapped CANH and CANL several times and never had any issues. I tried googling it and I haven’t been able to find any evidence that it should lead to damage. Also, looking at the datasheet for the SN65HVD232DR that you mentioned, it has the same limits for both pins, so I wonder how it could get damaged as a result of swapping them. Are you sure?