Can someone explain "deconstruction in the literary sense" to me in an ELI5 way, or even "explain like I'm a programmer with no classical literature degree and for whom English is a second language" way? Every time it pops up, I end up re-reading the Wikipedia article on deconstruction, and my eyes end up sliding over words as my mind fails to understand what's being talked about.

Deconstruction would be using tropes of a genre in a way which challenges their usual narrative function. It's related to subversion, but it also has something to say about the genre's implicit themes in general.

Undertale is an RPG where killing every monster you meet for XP is a very bad thing to do in the context of the plot. Perhaps killing everything in your path to succeed is not a good message. That would be a blunt example of how it deconstructs the genre.

NieR contains a medieval fantasy setting, a wilful protagonist, a dark mirror antagonist, "the power of friendship", heroic sacrifices, and secret endings. These are all staples of RPGs, but they're used here in ways which are subtly critical of the rest of the genre.

I don't have a literature degree either, so I don't know whether this is also the strict definition. But this seems to be how it's used in casual online discussions.