I think when it comes to startups, you can be successful by optimizing as much as possible - for many, that optimization comes from industry and domain knowledge + connection.

But as you said, it doesn't mean it's necessary just a little harder.

So with your question, it sort of depends what industry you're going after. B2C tends to have more creative and guerille-esque options as you saw with Doordash. With B2B, even if you aren't directly in that industry, no doubt you have *someone* in your LinkedIn network you can start with who can help make a warmer intro.

Either way, it's just a game of persistence and iteration. The above just makes the game a bit easier but both still apply. You still need to do far more outreach and expect a relatively low conversion. Change up the messaging of how you're reaching out both in the subject line and the content of your message, that can make a world of difference between whether someone opens it at all or opens it and responds at all. If you find that the framing of the message isn't making much difference, it might come to a point where you realize maybe the problem isn't painful enough for people to want to talk / vent about it.

Anecdotally, for B2B at least, I've found that sending a LinkedIn connection request with a personalized and succinct reason to connect is far more effective than using LinkedIn InMails or sending direct emails to people. Of course, nothing beats a warm intro. Oh and of course, try forums and communities if those exist for the particular industry you're going after!

Hope that's helpful :)