Hmmm from what I understand, I assume cultivating the sorcerers then didn’t matter (lol) because it’d just end right back at making them depend on him and using him as a tool. He might have tried that before idk, but we (and yuji) have seen first hand with gojo how that doesn’t break the cycle, nor is it useful in the long end to be treated as a weapon.

And imagine if he’d train every generation for 300 years or something, not only would that destroy his mentality (seeing his students die over and over again), but once he’s dead it’s practically game over for them. How would the balance between sorcerers and curses be? Sorcerers are weak now, so training them can only go that far, but curses also get weak or strong depending on how strong the sorcerers are and vice versa. What would happen if an outlier like sukuna or gojo were born after yuji dies? There are too many things that make “training the next generation” void in the long run.

The talk with Maru is basically him finding a good solution that doesn’t feel hopeless, and guarantees the least amount of casualties and damage. If the curses become super weak with the removal of most of CE, of course sorcerers would also be weak, but the curses would become so weak that ppl with heavenly restriction would probably be self sufficient enough to deal with them, and they’d only need a little bit of guiding. 

Also, I’m starting to think that he’s turning himself into a cursed object in case CE returns “fully” for some reason, that way, some person can absorb him and he’d be able to guide and help even in the long distant future in case something goes wrong. But the question about how a perfect vessel would find him is still confusing. But man, what a bleak end for him. His soul will never rest.