Well, we seem to be talking about kindness in regards to how it makes you feel.
Kindness does not work if it is forced. You can force people to do "kind" things, but that won't make them happy. Likewise, when we have unkindness built into systems, it doesn't necessarily make people feel bad, because they're being forced to do it (or at least, not as bad).
Yes. I think the key here is that it probably makes us happier to see two choices and choose the kinder, rather than simply living in a kindness-enforced society. At least for me, I derive a lot of happiness simply from my sense of agency, and choosing to be an agent of good will is powerful.
Kindness does not work if it is forced. You can force people to do "kind" things, but that won't make them happy. Likewise, when we have unkindness built into systems, it doesn't necessarily make people feel bad, because they're being forced to do it (or at least, not as bad).