Then I realized that the developmental / nurture model favored by most of today's intellectuals combined with brutal meritocracy does the same thing, but with a layer of personal blame and a huge quacky market for developmental aids of dubious effectiveness.
The fundamental issue is that society has become much more competitive and stratified, with the easier middle class path vanishing. That is going to create brutal competitive stratification regardless of what model (heritability or nurture) best characterizes the rules of the game.
Yet paradoxically we are in an age of extreme abundance where goods, services, and money itself (low interest rates) are cheaper than ever before.
Abundance is creating scarcity. Something is very very wrong.
It shows the heritability of intelligence at age 26 as 88%. Perhaps you're one of the 12% (forgive the statistically meaningless phrase - you get the idea). Or perhaps you underestimate your parents.
All of these forms of intelligence are genetically valid, but phenotype is determined by environment. You may get a great farmer, or you might get a researcher depending on environmental conditions...
So yes, they do matter a lot on outcome. If you haven't found a computer early, there could be a problem of you being outmatched and not proceeding alongside that path.
Developmental psychologists have brainwashed the public into thinking children can be ruined by insufficiency dedicated parenting. But for generations developmental psychologists were Lysenkoist hacks who didn’t realize their studies were confounded by basically all mental traits being extremely heritable.
The most important influence parents have on their children is at conception. If you want a smart kid, choosing a very smart mate is far more effective than any amount of mostly ineffective enrichment activities.
If you really care so much about the social status of your future children, marry well to a person high in the traits you value, preferably from a family high in said traits. Then have a lot of kids. Chances are one of them will achieve something!
Don’t get caught in the extracurricular signalling racket/cargo cult. Let the kids do what they want within reason. Public school will be fine. If you don’t want to ferry your kid around to various enrichment activities, don’t. Your time has value too. You care for your children; you do not serve them.
In most cases the kids don’t want to to do them anyway and will develop their own interests they will be far more enthusiastic about.