I know every distro has its own package manager, some of them share the same package manager, you can even install other package managers.
Besides the source there getting the content from, the formatting of the download and compilation phases, and maybe even a specific programming language; I still can’t wrap my head around why there need to be so many?
What rule says that every distro needs its own package and manager to install any package?
Aside from the technical problems you mentioned, it also solves the convenience problem of how to distribute libraries. C/C++ is really bad here because they dont have an integrated management tool. If you want to distribute over Linux package managers, then you will have to package it for every distro, paying attention to best practices and figuring out your dependencies for each one, you’ll also have to put it on the VS package repo for developers using Windows and possibly also support a Windows installer (and uninstaller) for those that dont use VS.
The alternative is to upload to a single repo and be done.