Wikipedia is the 7th most visited website in the world, more popular than Amazon, TikTok, even PornHub. It's not funded by advertisers or other bullshit - rather through reader donations.
With that said, Wikipedia is still centralized content whereas Lemmy isn't. Meaning there's fewer expenses and pressure on any one instance or server to succeed. And if one instance or server doesn't succeed, your access to the Federation is far from over.
A university is a typically a collection of colleges (or schools).
For example: Harvard University is made up of Harvard College, Harvard Business School, Harvard Divinity School, Harvard Kennedy School, Harvard Law School, Paulson School of Engineering and Applied Sciences, etc.
For all intents and purposes - we use the word “college” and “university” interchangeably because they’re the same level of education. Either can do associates through doctoral.
Community colleges, however, only focus on 2 year degrees and certain certifications.