I assume it has to do with getting a list of all Ailments and checking each one individually?
So the limit is there to not have to go through 40+ checks every X seconds?
Also assume that this is the reason more rare effects without synergy (like Future Strike) are excluded, because they cost the same resource as e.g. Ignite or Bleed, without being as useful for information.
With the last conversion bug I’m assuming that Ailments in Last Epoch are all the same base code and they just have a type(Bleed, Ignite,…) as parameter rather than them all being separate effects/scripts in nicely organised lists of which you could just get a length. Atleast, that’s what my ancient knowledge of coding and OOP classes make me think of.