Cybernetics is a harder problem than AGI and less rewarding. What is even the point of converting humans. Just make them sterile and give the last generation a great life. Artificial life forms then can continue the legacy.

Unless ofcourse it's not too difficult for an ASI. Then we will have billions of potentially malicious intelligent converted life forms with emotions and societal dependencies of an animal but god like capabilities. What could possibly go wrong with that. If it tries to get wise and convert with limitations then it's an imperfect copy and real being died, if it didn't it's hell.

(Sorry for the rant, got carried away)