to be honest this manga really goes bad, i mean a bad direction. MC was somehow too desperate or to narrow minded on the subject of sorcery compatibility. Considering that his old age, being such veteran in a combat and his vast amount experience gained , the only matters was that subject in his mind. Yet, he still does not see his own value or strength that he experienced during his travels with other sages.
If by my understanding , is that the MC does not have any affinity towards the general public elemental compatibility.Yet he goes reborn with the same situation which he is trouble with. However , out of nowhere he discovered that he had an affinity with Lightning
element and it is unknown type of affinity to the world. If it is correct, does not that mean , without even being reborn the MC have already the affinity of Lightning in the first place? if that the case, the story is going circles.