IIRC Huxley became rather sceptical in his later works regarding "eugenics" or in general "scientific dictatorship" as a solution to the social problems of humanity.
I may have to re-read his work "Ends and Means" sometime later, but I'm quite sure that calling him an "eugenicist" is too easy.
EDIT: fixed typo
He supported Muller's germinal choice scheme, according to In the Name of Eugenics, p. 262-263: http://pinguet.free.fr/kevles1985.pdf
What sources is it you remember?
One should also note that Aldous Huxley (like his brother) was a eugenicist, and people being distracted from performing their eugenic duties is a fear that echoes in his supposed dystopies. See e.g. https://archive.vanityfair.com/article/1927/10/a-note-on-eug...:
"[D]eficients are not only preserved: they are also permitted to multiply their kind."