I work in info sec, and in one of the "Who's Hiring" posts a few months ago (do we still do those? I haven't seen one in a while) I asked "why are startups never hiring security guys?", because I never see a security engineer position open in those topics. I never got a response. To me that indicates the response is "we don't". Listen, guys. I don't care how small you are. If you are handling PII or credit card data…
I'm gung-ho about security as much as you but the truth is that users hardly stop using a service after data breaches. The ones that do matter though are like the ones that delete all your AWS instances and custom AMIs when holding your company's assets for ransom. That is what startups should be worried about indeed (as well as enterprises that are transitioning more of their IT into cloud environments that can be scripted and automated much easier - makes it easier for attackers in theory too).