The thing that seems to be relatively rare about Debian among Linux distributions is that the packaging data is intrusive - a debian/ directory within the package itself, which must have already been downloaded. Most other distros seem to have external packaging - some sort of package specification that points to the URL of the upstream and is responsible for pulling it.
It cannot be overstated how much friction this inversion adds, whether for new packages, for updated upstream packages, or for distro-specific (hopefully temporary, but Debian has a bad record for that) patching.
(I actually tried filing this as a bug once, but it immediately got moved to the mailing list, and I promptly got un-CC'ed and stopped being able to reply, since what lunatic actually subscribes to a firehose of a mailing list? Email also considered harmful)