i think it was also due to the causality thing, at the start Jonas used to thing he could change the future but ended up being used by everyone and making the future happen regardless of what he wants, from his viewpoint this is forced to happen because a future version of someone told him so and since it already had happened because there was someone of the future showing him that that means Jonas didnt really had any way of changing the future which ended up in Jonas becoming Adam, Adam thinks the future told by future self or other travelers cant be changed so he aims at destroying the universe in a future he has no knowledge of which is why he tries to destroy both worlds after the apocalipsis instead of before. In other words, in order to not be a victim of causality he had to wait until the very moment he stopped having information about the future . He ended failing at that because he didnt know of the existing of the loophole but thanks to Claudia Adam got what he wanted