No one here can predict what Apple will do.
You can suggest it to Apple: Product Feedback - Apple
(They do not, however, accept unsolicited ideas.)
There are hosting providers that offer mail, web, DNS, and related services. Including deploying numerous apps. The hosting provider I’m using has multiple CRMs, ERP systems, and customer support apps all available, as well as numerous other task-dedicated apps. The apps are not tightly or cross-integrated. Not past cPanel or similar for deployment.
Closest to what you want for integration and self-hosting is probably NextCloud, though that too depends on add-ons for specific activities such as CRMs.
As for history, Apple got out of the server business (web, mail, chat, DNS, etc, though with no library of add-on apps ever available) with the end of the macOS Server product. The server-focused version of the macOS Server app ended at macOS 10.13, though a similarly-named and very limited MDM app lingered on for a few more versions.
Apple Business Manager and Apple School Manager are probably the closest Apple analogs on offer at present, and they’re very far from what you are asking about, and while they allow user management and app deployments and such, they don’t integrate user data across apps.