You know, the one thing that I think even PG would agree with is that the best way to figure out some of this stuff is to ship product, talk to customers, fix stuff, and repeat the cycle of shipping, talking, and fixing.

The OP is lucky they finally figured this out and shipped regardless of YC.

Getting VC or getting in YC can be great, but plenty of great businesses are built by people just putting their head down and building stuff.