System package formats (such as RPM and DEB) are linked to the Linux distro they were created on. There are tools for converting from one type to another, but we’re not taking those into account as they are not fully reliable. Even between distros from the same family, traditional packages are not reliably portable. For example, a DEB archive created on Debian may work on Ubuntu, but there’s no guarantee; even different versions of the same distro might be incompatible at package level. Portability of system package formats is poor. Snap is widely supported, particularly in the mainstream distributions. If it’s not installed by default, it can generally be added, but that does involve an extra stage for the user, and not every small distribution supports Snap. Much the same can be said for Flatpak as it does need support in the distribution. Flatpak is slightly better supported than Snap on distributions that are dissimilar to Ubuntu because it requires Systemd to work and AppArmour for full sandboxing. Even though it is similar to Ubuntu, Linux Mint is an example of a distribution that makes installing the Snap system difficult.