What we want for ourselves and our descendants is obviously not (or at least no longer) the same a reproductive fitness. The obvious example is contraception. It seems plausible that given environmental factors such as contraception and the modern welfare state that drug addicts might produce at an above average rate. That the human race might perpetuate under these conditions is no reason to rejoice about a future in which humanity is made up of crack-heads.
What we want for ourselves and our descendants is obviously no (or at least no longer) the same a reproductive fitness.
I don't think any non-human animal ever (consciously) wanted reproductive fitness as such, this being a long-term, multi-generational desire that humans may be the only animal capable of caring about, and I don't think all that many humans do. On second thought, maybe they do, in the sense that many humans want children and grandchildren. But the things we typically do want by and large enhance our reproductive fitness, so reproductive...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
If continuing the discussion becomes impractical, that means you win at open threads; a celebratory top-level post on the topic is traditional.