I had a long winding road through academia. Went to a big selective R1 state school in a different state after high school. Had an existential crisis, moved back home with my parents and went to community college for a year, finished my undergrad at a large, less selective R2 and then did grad school at a large, very selective private R1. I would rank the quality of instruction:

1. Community College 2. Probably a tie between the R2 and grad school. However, that grad school focused a lot on grad students, so it's possible the undergraduate experience isn't quite as good. ... 3. After a very large drop off the R1 state school.

You obviously can't extrapolate too much from my personal experience, but it does seem to line up with man others.