Sorry to be 'that guy’, but for SciFi, where it’s necessary to put to gether a picture of the world your characters inhabit (AKA 'world building’) that process needs to compete for space with things like plot and character development (if any, yeah, SF used to be pretty short on that). So an author needs to balance those, space-wise.

There are certainly SF authors who give a majority of space to world building, but very often those are one novel world per story. One of the best examples of that is Jack Vance. Lots of stories, each in a different environment and culture. At one point he tried to stitch that all together into something he dubbed "Big Planet", but a single planet wasn't big enough, so he came up with the "Gaean Reach" (a stretch of star systems in a comparatively small area in a much larger universe of inhabited places). But his characters don't develop much at all.

I'd agree on the huge span of 'worlds' created by Larry Niven. I'm a fan, particularly of his actually working physics - the first story of his I read had to do with tidal effects - and those were spot-on.