[throwaway20256]

I know there will always be boring work no matter what job I were to have; the issue is that none of the work I've done in the last year has been stimulating.

Your ideas aren't wrong, though the codebase that I work on is almost 20 years old, and making the code perfect, or even reasonably improving it, is going to require a lot more planning than a single engineer can provide. However, I will ask if this work can be delegated

I've brought up concerns about this to my manager (though admittedly in a tangential way since, again, there are reasons to avoid mentioning dissatisfaction that I can't go into). I have no doubt that the issue might be a feedback loop now; I underperform on the boring work and as a result I keep getting assigned worse work.

EDIT: I want to make it clear, I'm not trying to be defensive; I'll take criticism from your perspective and I appreciate the input.