This comment recalled for me the Bill Cosby joke which goes, "When I was a teen, I couldn't believe how stupid my Dad was. When my kids were teens I couldn't believe how much my Dad had learned between then and now." :-)
I didn't appreciate the wisdom in that joke until my kids were teens. The sadness comes from the expectation of the painful times between the onset of the technology and the eventual successful integration of that technology into our lives. For me, I live in Silicon Valley which has more superfund cleanup sites than pretty much anywhere because the chip companies dumped a lot of toxic chemicals that later turned out to be carcinogens into the ground. People I know, some well, some only by association, were harmed by that. It was part of the "learning curve" of developing semiconductors which have so changed everyone's lives. That the chips are a net good is, in my opinion, pretty clear. However, the "learning" of the superfund cleanup was painful.
Bespoke genetic manipulation will have similar "growing pains" and those pains will kill people, cause generalized harm, and likely a catastrophe or two. And once we've gone through that and understand the risks and challenges in a more fundamental way, then people will be enjoying the benefits and the risks will be contained by legislation or some other oversight.