A lot of the comments in here are about the debate on whether companies should be remote or in-person.
That's an important debate but orthogonal to what I wrote. The YC batch is not a company. It doesn't really have a close analogue, but if you forced me to choose, I'd say that doing YC is more similar to going to college than working at a company. And as all we all know, while many companies are staying fully remote, hardly any university is.
Having now done this back-to-back, I can tell you exactly the ways in which in-person YC turned out to be better than remote YC.
1). Most founders in remote YC didn't make strong connections with their batchmates. When I ask founders from remote batches "how many founders in your batch are you still close with?", they typically give an answer that's 0-3. When I ask founders from in-person batches the same question, it's 10+.
2). When YC really works, it's because it not only conveys some factual advice, but changes the way founders think and behave.
When founders go through in-person batches, they're usually significantly different by the end of the batch - tougher, savvier, and more formidable. Whatever causes that did not translate well to zoom.
3). In-person YC is simply more fun. YC has always been in part about being fun experience, because startups need to be fun or they'd be too difficult and demoralizing. Zoom is very effective for communicating information, but no one has fun at Zoom parties.