if the church of Jesus christ of latter day saints is the only true church than should not all christians become latter day saints?

No, but all Christians should find out for themselves if The Church of Jesus Christ of Latter-day Saints is the kingdom of God on Earth.  After that they should decide whether to embrace it or not.

That is the whole problem with religion. Even within one sect they still can't get their act together and agree on anything. 

The Utah Mormons lied that Jesus told Joseph to do polygamy . For Joe's own mom. son. & wife swore till death he never did that sin 

It might be their opinion that their church is "of Jesus Christ", but it certainly is not Jesus Christ's opinion. He founded one Church 2,000 years ago, said it was to remain one, and promised that one Church the fullness of God's truth until the end of time. He knew that truth can exist only in unity, because truth cannot conflict with truth, and conflicting beliefs therefore mean false beliefs. The Church Jesus Christ founded 2,000 years ago obviously must be able to demonstrate a clear history reaching back 2,000 years. Manmade churches that came into existence in the last few hundred years cannot be the one Church founded by Jesus Christ. And Mormonism is not even Christian. There is more to Christianity than believing "something" about Jesus Christ.

garbage in=garbage out.

That is a very massive 'If'. Until you prove the premise, the conclusion does not follow.

Again it’s how each person interpreted what he reads what they believe to be right for himself or herself if you just learn to treat each person with respect. All gods people are equal to god no one worse or better. Is that harmful to you or does it give you comfort that comes in a point in time where you will not have to carry your sins any further its called death. What happens after that no one knows or will they care.

Why can't I find Kolob with my telescope?

It isn't.  It's heresy.

Not true and no.