Imagine if Bitshares X were in Fedora, Ubuntu, Suse, Mint, by default?
Why not push to get it included along with Bitcoin?
I'm probably the expert on that, at least for Ubuntu and Debian, as I'm the one you would have to go through to get it included in those distributions.
To get into a distro you must address these concerns:
1) Legal: licenses must all be compatible and work well with others. Additionally, it must be "free" as defined by the DFSG (google DFSG for details)
2) Stable: software should be mature enough that it can operate without requiring updates to fix critical bugs that could break the system
3) Secure: the software should be built in such a way that will enable rapid fixing of security bugs
As an example, let's look at bitcoin:
1) Licensing is good to go
2) It is not too stable yet: mandatory hardforks can still occur at any time. If it was included by default on systems, it might be possible that a large percentage of machines won't update in a timely manner, thus hurting the network (and credibility of bitcoin). It is possible to do stable updates, but they usually involve a time lag that could exceed the expected hardfork time.
3) Secure: bitcoin requires building against an extremely specific version of a modified leveldb library to ensure network consensus. If a bug is found in the library, it is essential that the bug not be fixed until it is tested and included with upstream bitcoin code. As such, it is impossible to keep it continuously secure without also risking accidental forks or breaking consensus. Also, non-security fixes to bitcoin (i.e. network upgrades) may require rapid response. Distros are slow, on purpose, since a distro that is released is intended to be permanent and fixed to a specific version from the day of release. That's how Debian has the reputation of being one of the best and most stable servers you can use.
Because of those reasons, bitcoin is available in unstable repositories but not in any testing repository
2) Stability: no where near ready
3) Security: using nodejs introduces lots of external code, we would have to work to use debian nodejs packages rather than download via npm in order to leverage debian fixing security bugs on the fly. That's ok, just a decent amount of work. Also, the effects of using system leveldb would need to be analyzed
that's why bitsharesx at this time is not ready for inclusion in debian it ubuntu. PPAs are the best option for now, it allows continuous updating and the ability to have control over all dependencies.