Agreeing with you about the immortality of the soul.... however, the Evil Ones know their time is short, and that their souls will be judged and found wanting, and will likely not be found among the immortals of the saints in Heaven.
Because they know that, they are therefore quite interested in doing what is possible to extend their miserable earthly lives. FWIW
I’m not sure that many of the kind of people we’re discussing have faith in anything enough to fear the afterlife.