Listen, in essence, growth hacking is this. Instead of building a product and then marketing it, you understand that the product is the marketing; let that settle in. Your growth marketer should be involved from ideation phases right up to executing the whole GTM. You can't build a product and then say, "Here, now go hack some growth". All that brings is epic magnitudes of failure.

Growth hacking isn't finding a magical lever like airbnb, reddit, etc, you can't make non-viral product go viral, that's just forceful and any virality that is forceful and not innately built into the core functionality of the product just will never achieve sustainable growth, period. It's like all the nut jobs that talk about the k-factor and all that crap, it's complete bullshit.