Hi @ckneuppe, welcome to the forum!
Some casual observations do appear on the taxon pages by default. For example, if I observe a wild organism but do not have media evidence, the observation is casual, but it will still appear on the range map. For people who do not want to view non-verifiable observations on the taxon pages, they can uncheck the box next to “Observations w/o Media”:
The brownish orange color on taxon page maps indicates that the species/taxon is on a checklist for that place, but has no research grade observations on iNaturalist:
If you would like to propose a new feature, such as an opt-in option to display captive observations on a certain map, please submit a separate request to the Feature Requests category. There are some guidelines here: https://forum.inaturalist.org/t/about-the-feature-requests-category/69
Thanks!