This is an extremely reductionist take, to infer that all human progress is motivated by a better life for your children. Certainly some people are motivated by that, but human motivations are way, way more complex than this ridiculously simplified (and aggressively conservative) worldview suggests.
The assumption that society would "quickly crumble to dust" if children's opportunities were entirely independent of their parents' efforts and successes is quite possibly the most absurd take I have heard on this website in the 10 years I have been here.