I would gladly use only one package manager, but different applications offer different types of downloads. Do this for 30 applications, and you will probably need 3-4 package managers or install methods that do not auto update. Example:
- Firefox: ppa, because that has always been the fastest and most convenient
- Krita: flatpak, since the others suck
- Qbittorrent: only AppImage
- Godot: native executable