explicit plugin inheritance not working in meltano

I have multiple tap-postgres-based extractors in my meltano project, so would like to name each descriptively and have them explicitly inherit from tap-postgres. According to the docs, I believe something like this ought to work:

plugins:
  extractors:
    - name: tap-postgres--some-descriptive-qualifier
      inherit_from: tap-postgres
      variant: meltanolabs
      pip_url: meltanolabs-tap-postgres~=0.2.0
      config: ...

However, this raises an error on install, and doesn't actually generate a lockfile:

$ meltano install
Extractor 'tap-postgres' is not known to Meltano. Try running `meltano lock --update --all` to ensure your plugins are up to date, or add a `namespace` to your plugin if it is a custom one.
$ meltano lock --update tap-postgres--some-descriptive-qualifier
Locking 1 plugin(s)...
Extractor tap-postgres--some-descriptive-qualifier is an inherited plugin
$ ls plugins/extractors

As a result, I can't run the plugin:

$ meltano invoke tap-postgres--some-descriptive-qualifier
2025-05-29T20:25:23.174730Z [info     ] Environment 'dev' is active
Extractor 'tap-postgres' is not known to Meltano. Try running `meltano lock --update --all` to ensure your plugins are up to date.

I've tried a half-dozen different variations in the meltano.yml file, but nothing works. Assuming this is user error, but I am stumped. I'm using meltano v3.7.6 btw.