This is my point, you can get this advice easily outside of YC.
I disagree. There are a lot of experienced people willing to learn about your business and provide you valuable insights but in almost all cases, they have some interest of future gains - such as investing in a future round.
When that is not the case, it is still pretty rare to get someone experienced to really get involved in your business and offer non-generic advice over a prolonged period of time.
- meetings with the best VCs
These could easily dry up if the yc batches do not maintain their perceived high quality. I'm not saying it will happen but it must be a concern?
- tailored advice from (more and more) folks who have done it again and again
This is my point, you can get this advice easily outside of YC.