A distro package manager provides access to a small set of packages that the distro thinks you might like. A language package manager provides access to the full set of packages. The language level package manager is solving a more ambitious problem.
Distro package managers don't solve the problem they just punt on it, saying "you can add an unofficial source but you're on your own to maintain security". I agree with GP that the comparison is tiresome.
Debian stable has over 69,000 packages, which is more then some languages have…