I personally see a big difference between developer, funder , builder , and owner. Maybe this proposal will help clear the confusion and actually differentiate between these tags if each of them is properly documented.
Developer: The company or organization responsible for planning, initiating, developing and eventually marketing and selling the project in order to make profit, e.g. real estate developers.
Funder: The entity that provides the funding for the project, e.g. governments, banks, NGOs, or private investors.
Builder: The company or contractor that physically constructs the structure, e.g. construction companies.
Owner: The current legal owner of the object or land, e.g. individuals, companies, or public institutions that own the asset.
developer and similar tags have more than 11k uses.
builder has 2815 uses and funder has 57 uses. What do you mean exactly by “reasonably well-established keys”?