So genetic modification would be a solution to this.
For some. The 'problem' is that humans choose their own values and they very often do it based on their instinctive payload more than anything else.
How many people do you know who would voluntarily (and permanently) give up their sexuality?
Now you can say "well you won't miss it if you've never known it" but you could say the same thing about eye sight or hearing. Most people enjoy being sexual creatures and they're going to want their offspring to have the same chance.
If anything any requests for asexuality will be greatly eclipsed by request for healthier and more rewarding sexual traits.
As I always point out, it's taken approximately 300000 years to get this far.
and 10,000 years is a blink in the evolutionary eye, but at the rate we can now collect and analyze information we're going to be able to anything we want (within the bounds of what biology has already demonstrated) in 5000 years (assuming no collapse of technical culture).
We don't need to wait till then to know what people would want to do though. They don't want "a limited colony of super-intellectual, asexual humans." Specifically the asexuality or anything else that is a denial of what the Greek philosophers might call "the good things in life". ("super intellectual" has nothing to do with asexuality.)
Humanity at large probably won't use force to stop it, but there is no way they'll all choose that path or tolerate any attempt to force them in that direction.
I am one of those people BTW, we could eliminate sexuality and then next taste, but the only possible motivation I see is a deeply irrational notion that the farther away from evolution's inheritance we get the more perfect we are. It's more like the more robots we are.
Perfection would be completing the pattern. Taking the good evolution has made, enhance it, mitigate the bad as far as possible.