As it has been said so many times, tech privacy aware people are the minority. It won't make any difference for my non-tech neighbor (in fact, he will probably be delighted if it helps him with something).
(I agree with the point, but it's just not trivial to make people aware of this)
Most would submit genetic material to 23andme and similar organizations with no restriction on its use. Yes, if could theoretically backfire not just on them, but also on their kids. But unless they see it as a near-term likelihood they will not care enough. My 2c.
It's abundantly clear that most people don't care about how their data are used. Here "most" means people outside HN.