What does trivially reducible mean?

A PRNG is inherently complex and winners of https://www.ioccc.org/ are a class of complexity you deem reducible. This competition involves building complexity and since there are winners it's feasible to claim that to win it is "hard". Since this straddles a form of art, placing a value judgement as easy vs hard seems invalid.

The reason I'm thinking about this is because I recognize that adding accidental complexity is far easier than removing it. In fact, I spend a significant amount of time "trivially reducing" such complexity.