The "divMod" function is good. You could write:

          (m, rs) = s `divMod` 60
          (h, rm) = m `divMod` 60
          (d, rh) = h `divMod` 24
          (ry, rd) = d `divMod` 365

which is nice.

Ummm... the Writer monad exists and any list is a monoid so "DescriptionStore r" is isomorphic to "([String], r)". You don't even need to import anything other than Prelude to use the latter as a monad.

But I like your approach (porbably because I had a similar idea, lol).

Whenever I run my function on my laptop, it computes instantly, even for enormous inputs.
Whenever I try to submit it, I have an "computation time exceeded" error.

Can someone provide images of example of input and the output for said input? From what I understand, the task doesn't require the world's time to pass, we just crop dead cells off.

I admire your solution