In a world with mandatory genetic testing, genetic engineering in order to "give your child the best possible start" will definitely ring true.
If you could though, if you had a clear understanding of how Trait A and cluster of genes/epigenetic factors Z were related... then what traits would be valued? Some would want attractive, intelligent offspring. After a while though, I wonder if people would really want that?
If you're the kind of person who wants to control the development of your kid's moral/religious/political/etc. views (and lots of people do) then you're not going to get what you want out of that. You might want to select for traits that are just... like you.
For example, when parents perceive the economy to be closer to zero sum, with clear "winners and losers", they tend to push their children more to get every edge they can in credentialing and jockeying for the best position for financial security (read: Tiger Moms).
Hard to say what said environment will be in the future when more tools are available.
Then you might need to breed a very different kind of mind.
Who knows, pale skin may sadly be more desirable than ever before if things continue their current course. :(
Then of course, maybe they'll all die off. Breeding is a tricky business, as any farmer or botanist will tell you, and at least there you're taking it slowly.
Except that you could do it at a genetic level. People, like Pugs and Pomeranians, because that's how we do things. We'll create fashions and fuck around before we figure out the fine details.
"Oh Mandy is so lovely and pale, so thin and tall! What a pity she slobbers and can't breath very well."
Even worse, lets imagine...
Uganda bans "Gay genes"
Parts of the world now produce girls who are naturally born "pre-mutilated", or maybe you bypass that and just make them unable to experience sexual pleasure.
Maybe people would finally get their dream, and have a child who would stay a child for a very long time.
Then you have the people with a plan... the "best golfer" or "best football player" stuff, but now genetically loaded before conception. Todd Marinovich, but even more intense.
Just take all of the insane, controlling shit that people do, and now give them as much control (and as much fallibility) as you can imagine over our own genes.
That's an understatement that belies human laziness. The real predictor of success, almost no matter how you define success, is about the effort you put in. Good genetics is usually a micro-optimization on effort expended. But if you ever told people that they were genetically Destined™ or Guaranteed™ to succeed, that's precisely what will cause them to discredit effort, sit back on their laurels, and wait for the not-so-inevitable money to start rolling in. When it doesn't, their failure will breed resentment and conflict.
> I wonder if people would really want that?
People want to be at the intersection of attractive and unique. Attractive is more or less easy to control for - genes for attractive figures, full heads of hair, clear skin, no disabilities. Unique is far more difficult, and would only get more difficult if sizable pluralities or majorities of parents started to select on the same Recommended™ or Best Choice™ genes, and generations start to look like cookie cutter clones of each other. Most probably, you'd end up with some classic tragedy of the commons, and the government would have to step in to regulate what would end up being a finite resource (being genetically unique, with a genetic monoculture being especially dangerous considering the Darwinian requirement for genetic diversity to promote survival) if the market's natural price pressures didn't self-correct. And if you think the rich and powerful will allow the government to allow anybody but their children to have the beauty and desirable qualities which will keep them at the head of their parents' empires, well, I have a history book on feudalism to sell you.
That, and how well you choose your parents. Unless you honestly believe black people just didn't try hard enough to be president for the first 230 or so years of the USA's existence.
Christ these Horatio Alger "just so" stories are ridiculous. And if we repeal GINA, it'll make it that much harder for people to escape their supposed "destiny". Genetics interacting with environment makes us who we are. I'm of the opinion that the latter is more important, and I hold a doctorate in statistical genetics so this is not purely an off-the-cuff opinion. It may or may not be right in a specific case (evidence >> eminence, credentials are at best a proxy for expertise) but it happens to agree with yours, if you think about it.
The amount of grit you develop is going to be a function in large part of your childhood (or other major environmental influences; in the field, "environment" is shorthand for "everything that isn't genetics"). So locking in an ignorance of its importance is just astoundingly stupid. If we want a sclerotic European aristocracy or a caste system in America, this is the way to get it.
And of course the rich and powerful will do anything to perpetuate their position. On average, however, the American dynasty half-life is 3-4 generations. Compare that to Europe and I think we know which better favors social mobility.