

I drink milk, but milk isn’t superior to oat milk.
mammal milk has specific ingredients that are meant to specifically feed infants of that animal. So its often high in fat and has specific things that are meant to be digested by that animal. Breast milk from a human has special ingredients that help digest the high lactose content and those ingredients are not in other milks.
Now Oats have been designed over years to be digested by humans and other animals. They propagate by being consumed and then travel to other areas post consumption. The nutrition in oats and other vegetables is mostly there specifically to drive animals like us to eat them so that we propagate them.
SNW S1E2 - Children of the Comet. This is a tricky one because of potential predestination and the end result being an accidental major break of the prime directive. A warp capable civilization is certain that a comet must destroy a pre warp civilization and refuse to let that change. The issue is that the ship/comet wants the Federation to interfere and does not intend to hit the planet. This is all in Federation space.
Another in Federation space that is also a loose fit is LD S5E7 - Fully Dialated where the crew must recover Data’s head from an alternate reality that has fallen on a pre warp world. The loose fit here is that the only reason they count as external is that it is Purple Data who is not technically a a member of this realities Federation and thus an outsider.
Lastly a decent fit but outside Federation space is Prodigy S1E7 - First Con-Tact. The crew first breaks the prime directive by making first contact with a pre warp civilization but then defends it by stopping a Ferengi from influence the civilization negatively. This is outside Federation space though.