Partial agree. YC created HN, though the HN community is very much _unlike_ anything I've seen at YC.
HN is deeply skeptical, technical, cynical, sarcastic. It's a great place to learn new things and I've loved it since I found it in 2012.
The current startup climate (not just limited to YC) feels very AI bro YEAHHLETSFUCKINGGOO (and I say this as a founder myself having gone through YC recently in W25).