I sure as hell am supposed to. A big, floofy one.

It's not totally vestigial, it helps regulate colon bacteria. People without their appendix take longer to recover from diarrhea, which is important when bad water and spoiled food are a more regular part of your life.

Their genetics have sacrificed nearly every aspect of basic resiliency for maximum speed on the plains. Most of the work caring for horses is keeping them from accidentally killing themselves. Full disclosure: I worked as a stable hand as a child in exchange for riding lessons. Will never ever own a horse.

Sometimes they will die because they can’t puke. Also broken legs are usually fatal even with vet care.

The term healthy as a horse is mostly survivorship bias

You stand on your toenails

It is, they have hooves.

From an evolutionary standpoint we just have to survive long enough to reproduce, if we can't eat past age of reproduction there's no evolutionary pressure to change that.

Thank goodness for modern dentistry.