That’s because in the old world, social cohesion was the most important factor in your group’s survival. Anything that got in the way of that, like neurodivergence, being otherwise different, or not having children with other members of your group when it was expected, could endanger your survival*.

Thankfully, we’re not in that world anymore, and the differences between our world and the one in which those rules/laws arose are what make morality developed during that time irrelevant. We can explain why murder is still wrong today without relying on religious texts for justification, but we can’t explain why eating lobster is more wrong than eating beef anymore, nor can we explain why just being different is wrong anymore.

The people who made those laws lived in a rapidly desertifying climate before refrigeration or indoor plumbing - if your group wanted to eat lobster, they would have a lower chance of survival overall. You can find reasons like this for most religions’ rules, and some of them, like banning murder, still contribute to our group survival, but that’s not a reason to assume any given religious prohibition is sensible today.

*to be clear, I’m not suggesting that any of those things were actually wrong or inherently contrary to a group’s survival, because many cultures had no issue with weirdos, neurodivergence, or queerness. The people making these rules probably believed they were good for their group, but they didn’t have access to the information that we do now, nor did they have the benefit of the intervening millennia of philosophical developments. The groups that prohibited queerness and observed dietary restrictions were also trying to separate themselves from the groups around them, to strengthen in group feeling, and they enforced it later when converting new groups as a way to mark a clear cultural shift from the old ways.