Reverse dependencies reported differently -- "dist" versus "module" -- for same CPAN distribution

[jkeenan]

Suppose I go to the "pod/Some::Module" version of a CPAN library's home page: https://metacpan.org/pod/Types::Serialiser

Now suppose I click on the "reverse dependencies" link: https://metacpan.org/module/Types::Serialiser/requires?size=200

I see that there are (approx.) 19 CPAN distributions that depend on Types::Serialiser.

Next, suppose I go to the "dist/" version of that same CPAN library's web page: https://metacpan.org/dist/Types-Serialiser

... and now click on the "reverse dependencies" link on that page: https://metacpan.org/dist/Types-Serialiser/requires?size=200

I am taken to that URL but am told:

Distributions Which Depend on Types-Serialiser

No distributions depending on Types-Serialiser could be found

As @grinnz note on #p5p, "not sure what "revdeps of a distribution" is supposed to mean but whatever it is doesn't seem to work, anyway".

However ...

With a different CPAN distribution I get lists of reverse dependencies whether I start from the "pod/Some::Module" page or the "dist/" page -- but not the same lists. See:

https://metacpan.org/module/List::Compare/requires?size=200: 37 revdeps

https://metacpan.org/dist/List-Compare/requires?size=200: 40 revdeps

The module version lacks 3 distributions found in the dist version:

$ diff dist-revdeps-20211004.txt module-revdeps-20211004.txt 
3d2
< Algorithm-QuineMcCluskey-1.01
20d18
< Logic-Minimizer-1.00
22d19
< MarpaX-Languages-ECMAScript-AST-0.020

Can you explain this anomaly?