i second this-
his entire MO/logic can be summed up as "humanity is fucking the environment, i need to wipe out enough of humanity that there arent enough left/ enough infrastructure left to actually fix the damage dispute their industry slowly becoming less and less damaging over time,and their willingness to reduce/repair the damage also increasing with every decade, which will magically make all existing damage to the planets ecosystem vanish the moment i hit a few petastalins worth of casualties!
SURELY nothing bad will happen without people to maintain/slowly process dangerous waste, or to shut down/maintain nuclear facilities,chemical waste storage tanks near aquifers/rivers/oceans, no sir!"
he's, at heart, an intelectually dull to mediocre at best (albiet superficially charismatic at times),psychopathic caveman who's never had a reason to sharpen his intellect in his entire life, with a painfully naive belief he can solve a complicated set of problems with his trusty old club/hand-knapped flint spear/axe to the back of peoples skulls- he can just save-scum through almost any threat/failure until something succeeds through sheer luck- one of his plans to "save the environment" was a fucking orbital kinetic weapons satellite intended to wipe out most of humanity, which would somehow not fuck the environment further!
i think thats what i dislike about him the most, really- he was essentially a nobody who got lucky and won the immortality jackpot, and proceeded to spend the entirety of recorded human history wasting it/using it for stupid or petty reasons....
i think the only time he EVER improved in any canon was that time he succeeded, accidentally killed everyone and everything, and spent centuries going insane/recovering/going insane in a loop from complete isolation until sanity finally stuck as the fact that he had a problem where "kill myself/get killed, try the exact same thing again" wouldn't work slowly seeped through his skull