All that time fussing with aliases, turns out you can just straight up set the category page's URL in the front matter:

---
title: "Perspectives"
description: "Essays off the beaten path, mostly political in nature at the moment."
url: /perspectives/
menu:
  main:
    name: "Perspectives"
    title: "Perspectives"
    identifier: "perspectives"
    url: "/perspectives/"
    weight: 10
---

*Essays off the beaten path.*