Feature creep
Also said as Featuritis, Kitchen sink design
The game collecting more and more features, because each sounded good, until they crowd each other out and the original idea is hard to find.
Every pair of features has to be tested together, so the testing grows far faster than the feature list. Players also have to learn all of it, and a game with everything often feels about nothing.
Say it
“We do not need crafting, or fishing. Name one player problem each of these solves. If nobody can, they come out, because each one adds to every test pass.”
Where you’ve seen it
Duke Nukem Forever was announced in 1997 and released in 2011. 3D Realms moved engine early on, from Quake II to Unreal, and kept reworking the game to include what newer games were doing.
Not to be confused with depth
Depth comes from a few rules that combine in many interesting ways. Feature creep adds new rules that mostly do not.