For a long time, there was a pax debiana in my world. I used Ubuntu mostly (swapped to Debian and added Fedora towards the end) and the package management was really good. APT was a great tool and I got quite chummy with its ways. It was straightforward to keep my system updated and resolve dependencies. It was way smoother than any other updater system had been, even across major system upgrades.
I sort of lost it when snap started usurping stuff. I knew it was coming, because docker was already making inroads. Then we had flatpak and company. As an admin, as a system architect, I felt that's the point when I lost control of my system. It wasn't possible to know its update state anymore. It wasn't possible to centrally manage or monitor those updates. It became a free-for-all of self-updates and shadow updates. Ubuntu was also introducing livepatch and kernel updates that went outside the apt model.
I think that perhaps it became too great a burden for the major distros to be packaging all of their own downstream packages. Perhaps they saw the opportunity to offload some of that packaging burden on a really pro service that could just package everything, and make pan-distro packages available. If Debian and RHEL packagers are doing less downstream packaging, then perhaps they could focus on their core competencies. I noticed that nearly every Ubuntu package needed to include Ubuntu-specific tweaks, and basically when Ubuntu was already downstream from Debian, why should Canonical be maintaining every damn package themselves as well?
So what's the endgame for all this? Would apt or dnf/rpm eventually get abandoned and have them go all-in on a new system? Or does the proliferation and splintering continue? Many of us said that the beauty of Linux is our freedom of choice. Well there's too much choice. Look at Distrowatch and be paralyzed by not knowing what to choose. Windows or macOS on your desktop is easy to choose because there's... one of each.
When I visited Catalonia my friend took me to Carrefour. We strolled the aisles and I spotted pig-legs (jamon serrano) on every counter. A huge selection of eggs. Everything my stomach could desire. She led me into the olives aisle and gestured around to all the olives there. She said pick whichever I want. There were so many. They were all in fancy jars. I knew nothing of olives. I left without choosing any.
Linux will die a death of a thousand cuts, until some consolidation and unification can happen that's beyond the kernel.