This is how I view segulos, and I may be right or wrong, but it is my personal view:
Segulos such as learning or reading Perek Shira, Iyov, Shir Hashirim, or whatever, are not done to “force” Hashem’s Hands, as if we ever could. They are done to make us more acutely aware of our connection to Hashem, and hope that by doing these things, we accrue some “brownie points” that make us more zocheh to hear a “yes” than we were the previous day. Some segulos or so-called segulos are naarishkeiten, but others, such as the learning, or having forty women (40 being one of a few mystical numbers in Judaism) be mafrish challah and bake it the same day, as a segulah for a refuah for someone, are not naarishkeit, because they either cause us to do more learning, or bring people together to do a chessed and make forty brachos shel mitzvah in the ZECHUS of the choleh, and it is the CHESSED and achdus (not to mention the many brachos), not the baking, that is the real segulah, in my opinion. Hashem always looks favorably when He sees His people caring about each other.
Because someone does not feel the need to partake of such things, is neither right nor wrong. It simply is that person’s derech. As long as something does not in any way NEGATE halacha, I don’t think it causes any harm, and often causes good.
Btw, isn’t the giving of tzedaka a segulah itself to be a shmira against death? Just a thought…