Regarding the remains of the soul

Shabbat Shalom Miki, it is known that many Rishonim, led by Ralbag (at least he refers to this directly and clearly) believe that a person’s thoughts and experiences (which coincide in the Hebrew Bible with the “acquired mind”) are his soul and do not go anywhere when a person dies. This theory has many practical implications regarding the principles of faith (is the unbeliever in whom he has no part in the world to come a “punishment” doctrine or is it a reality that his mind does not perceive eternal thoughts and therefore is not eternal)
In any case, I would like to ask whether you accept this theory and if not, why, and what would the soul be like if not for the above.