And lots of big developers will have the telemetry data (achievements being a small visible surface cut of that pie) to know what players actually did or didn't do a lot of on that last go round to inform some of those factors the next time

Thing is 'fully featured' is an entirely subjective and entirely in constant flux based on what the developers want the experience to be and what each individual player likes or equally never bothered with.

What one thinks everyone uses may've actually encompassed merely 5% of the base.

Because old features don't suddenly not cost time and resources all the same, and don't necessarily code the same just because sequels are often good at making it *look like they did* and still go on high-to-low prioty lists

Haha yes, to be sure

Hahaha

The one time I actively tried speedrun stuff was trying a few early skips in Metroid Prime 1. Technically also achieving the under 3hr Hard Mode bonus for Metroid Dread kinda counts too but those aren't long games anyways and I really loved both.