You can bash Christians and leaders all you like, but ... that one verse you claim teaches reincarnation ... is not making a case...

If that were hinted at a few times in a few places, you might have a point, but it doesn't. That is the only verse that could even vaguely mean reincarnation.

And it is more likely jesus was speaking of the spirit of Elijah, and not the literal person.

Or maybe it was. who knows

but one verse like that out of context does not a doctrine make... cults have been started that way.

I see a lot of people bashing christianity because some leader did not agree with their interpretation.

The better response would be to study it and use actual real study methods to prove your case.