New people are being born all the time. There are many industries based around one time purchases. Think appendix removal or weddings (that one may be more than once for some people)
23AndMe saw tremendous growth, both according to the article and my anecdotal experience, but that doesn't mean that the burst they saw was sustainable. It's looking, at least right now, like it's not.
Not always, possibly not most, but many.
[1] https://www.lendingpoint.com/blog/appendectomy-what-it-costs...
Maybe we could make it elective and pump those numbers up to grow the addressable market size to all Americans
https://www.sciencedaily.com/releases/2017/01/170109162333.h...
Before all the privacy concerns, I was considering getting my kids tested, even though my wife and I have both done it.
Mainly so that I could see which genes they picked up from each of us and if they got any new mutations.
Also, a situation that might be somewhat niche -- we had IVF, so it is possible there was a mistake in the clinic and the child wasn't made from us. I read too many stories about IVF clinics where the samples were switched by the employees with their own.
Even more mind blowing, through sheer clerical error, the children that came out of my wife could be mine but not hers!
Given that they look like us we're pretty sure the clinic didn't screw up, and at this point I would keep them regardless, but if I could discover an IVF mistake, the settlement would make for one heck of a college fund.
Gee, how magnanimous of you...