The bill split evenly can feel unequal when people had different freedom to order.

An even split treats everyone as though they arrived with the same room to choose. One person ordered without looking at prices; another picked the cheapest main and skipped a drink, then paid the same amount. Nothing unkind was intended, but the arithmetic quietly transfers money from the person with least to the person with most, and the person with least rarely feels able to say so.

Offer to split by what people actually had, and offer it before the bill lands rather than after. If you are the one who ordered freely, say the fair thing first so nobody else has to. It takes one sentence.