If there's 10-15 players in the space and you're the one with YC connections...
Meanwhile if there are barely any players in your niche you have time to get things wrong and iterate in isolation, no need for the all-or-nothing style of growth
And since customers are the most difficult part now (because 10-15 players), it adjusts the relative value of something that doesn't help you acquire customers.
IOW, the differences between a "build it and they will come" historic era and a "make me care about you" modern one.
> a lot of YC advice, especially w.r.t. what to prioritize, is from an era of startups about 10-15 years ago.
I'm saying any misalignment in strategy matters less than implied. I spend a lot of time with current and past YC founders these days, and the recurring thought has always been "if you know already know business they're not going to teach you that much".
> it adjusts the relative value of something that doesn't help you acquire customers.
Money is how you acquire customers. From outlasting competitors to advertising to improving your product, it's money that turns into customers. So YC being valuable for investing is tantamount to being valuable for gaining customers.
This, however, not so much:
> "You basically need 1-2 full time staff doing nothing but content creation and social media outreach marketing"
If that's the way you're thinking, YC's going to try to change your mind, and if you don't want to change your mind about that, YC's probably not a good fit.
(I'm not speaking for YC here! just from my own experience as a founder, observer, HN mod)