Barring genetic modification to allow Homo Nano to survive better in a non-notum environment, it would be a simple matter to end notum infusions in solitus fetus while allowing for genetic reversion to Solitus gene stock in full adults (akin to how it is still possible to transform others into Atrox, only this would be the reverse, back to Solitus).
Why anyone would view this negatively is beyond me, as it would benefit the Homo Nano individuals greatly, if it came time that there might ever be an issue with survival on Rubi-Ka. Even then, it would break the shackles that holds Homo Nano to this planet, allowing freedom of travel once more.
Attempting to argue that there is some culture or ethnicity behind the Homo Nano breed is silly. We are Solitus modified in the fetal stages to be Homo Nano. Were it not for the intervention of a doctor during my fetal cycle, I would be Solitus, as would every other Homo Nano. This lends me to support myself as being only one type of being, a Human Being, not a Homo Nano.
The only reason I can see anyone arguing to continue an essentially flawed design (the inability to leave Notum rich Rubi-Ka being the major flaw, though there are physical weaknesses) is to retain the power of our natural nano-bot control. It is powerful indeed, and many Homo Nano avail themselves of this are are Doctors, Nano-Technicians, Meta-Physicists, and Bureaucrats.
When survival is on the line, a being with any amount of enlightened self interest chooses the path of life over power. If I were forced to make the decision today... Take my chances of death on Rubi-Ka or become Solitus, I would make the choice without hesitation to return to my Solitus stock roots.
Perhaps I may not be as 'powerful' a Bureaucrat, but I know even Atroxes that have mastered the profession, so find it no great leap to assume I will not be greatly weakened in any way.
((OOC: According to the only information that is available, Nanomages are created, not given birth too. My belief is that if two nanomages couple, they will produce a Solitus.))