I have no issue with that personally but it's not always practical. eg:

- people with Window seats next to families

- occasions when younger kids have been sat for so long that they're now fidgety and causing a disturbance. With the best will in the world, sometimes physically restraining kids is just going to cause more issues then letting them disembark the plane

- if the family have large items in the overhead storage that needs removing so someone else can get their luggage. By the time you've juggled all that luggage around, the family might as well just join the queue of travellers waiting to exit

It was also mentioned that individuals should not be sat next to families but that doesn't always work when you're trying to fill capacity and/or let travellers pick their own seats (as many flight operators do).

Sadly what is academically optimum isn't always what's practical in the real world. If that were true, there would be a lot of efficiencies the human race could made from road travel to financial savings.

I'll add, as father of 1 year old who had been traveling a lot, sometimes you need to run for a connecting flight because the previous one is very late.

I usually board first with the family (required, I don't have enough hands to hold the baby and put luggages above, and my wife is not tall enough), but whenever possible I leave the plane last. It's relaxing, no one is chasing me, I can grab the bags slowly while preventing my baby from killing some one

That leaves people in window seats bottlenecked behind families.

Don't seat non-family members there.

And because of all the edge cases and special rules that have been established, we can see why this isn’t a practical approach.

The number of people who are traveling with families is not a trivial number of passengers.

So far we have 2 rules:

- Seat families towards the hull of the plane

- Have them exit last

I don't see a plethora of edge cases here that make this not practical. In fact, this seems very practical to me.