I think we all, in our dim humanity, wish Christianity was a democracy, but it is not.
It is a monarchy.
And the Word of the King, in this monarchy, actually IS the King.
So, the Word of God tells us that men are given “once to die and once to judgment” —nixing the idea of reincarnation, but also pointing that the time to be judged for what we do on earth ends when we die.
... and that same living Word also tells us that necromancy or prayers for, or to, the souls of the dead is not tolerated, but a sin.
“Half of Chrisitianity” may believe prayers for the dead would help but they have been out-voted by the King (of Kings)...
God is His living Word who “was God and is God” and also “the Word that was ... made flesh and dwelt among us.”
Meaning (at the very least) that the words of the King cannot be broken by a majority vote of His subjects.
Praying for people after they die, unless you are thanking God for the person whom you love that is now gone, is pretty futile. This is why we are to “preach the word in season and out of season” and cry out for the harvest of souls — now.
Wait ... you mean the Mormons getting baptized for all those famous dead people is sueless? ... Does Salt Lake City know this? /s
You express well the ideas of your sect of Christianity.
Still, the orthodox faith,, Christianity before the Roman church split off explians it like this,,
“in what sense do we pray for the souls of the departed? Why, in the same sense that we pray for the souls of those with us because Christ is Risen, trampling down death by death. The barrier between living and dead has been eliminated due to the Resurrection of Christ. Those who are departed are just as much with us and just as much a part of the Church as those who we see living on this earth. There is no longer any separation. And so not only do we pray for them, but they also pray for us; in the same way that you might ask your friends to pray for you and in turn pray for them, so also do we pray for each other without concern for the separation of death.
When we pray for either the living or the dead we use the same prayer: “Lord have mercy”, to express our desires. We do not know what to pray for, even for those with whom we live, because only God knows what is best for our salvation, and so we say “Lord have mercy”. Likewise we do not know the needs and concerns of the departed, but God does, and trusting in His knowledge we say, “Lord have mercy”
We do know that, like all of us, those who have departed require forgiveness of sins, and that they look for a “place of rest” in the bosom of Christ and so we make this petition, that God will provide these things, but again as for specifics about how this should happen we simply conclude with “Lord have mercy”.