If Lehi were to show up amongst the LDS Church today, the Church would treat him just the same way the Jews treated Lehi. Allow me to elaborate.
You don't have many people called Lehi today. So imagine our protagonist is named, say, Brian. One day, Brian has a vision. In that vision, he learns that if the people don't repent, they will be destroyed. In Sunday school the following week, he says so. "If you don't repent, you're going to be destroyed," he says. The following Sunday in Fast and Testimony meeting, he says the same thing. And, for good measure, he posts a like message in Facebook and on his blog. After all, in his vision, he was told to warn the people.
Next thing he knows, he's called into the bishop's office. The bishop reminds him that he can't receive revelation for the ward, the Church, or really anyone but himself and his family. The bishop lovingly tells him to stop with his repentance message. Brian tells the bishop he's been charged to preach repentance by a higher authority than him, and vows to continue.
The bishop reports this to the Stake President. The SP calls Brian in for a meeting. In the intervening Sunday, Brian preaches repentance again in Sunday school. This time, the member who had been whispering things under their breath, now are a bit more vocal with some "sit down and shut ups" heard. The Relief Society gossip network has kicked into high gear with damaging stories about Brian. The stories are full of sorrow toward Brian's wife and how much she must be suffering because of Brian's actions.
The meeting between Brian and the SP goes much the same way as the meeting with the bishop. Only this time, Brian is told that he is committing apostasy. Brian, amazed, asks how this is so? The SP tells him that by continuing to tell people (and their leaders) to repent, now that he's been counseled not to, he's "committing" apostasy. Brian tells the SP he will continue to fulfill the responsibility given to him in his vision.
The following Thursday (4 days later - these happen very quickly), Brian is excommunicated from the LDS Church for apostasy. Brian, however, is not deterred. He continues to show up on Sunday and preach repentance. By now, the calls to "sit down and shut up" are vocal. Jeff's kids are having troubles with their peers in Sunday school and the Relief Society gossip network has gone from being sorrowful for Brian's wife to pointing out some of Brian's wife's flaws and maybe she is somewhat responsible for this - wasn't she always just a little bit strange. One sister observes that this Brian and his family were always a bit unstable and, doesn't he own a gun.
Later this week, Brian get's a letter from the LDS Church law firm. The letter tells Brian if he steps foot on LDS property anywhere in the world, he'll be charged with trespassing.
I'll stop the story there. I'll leave it to you to ponder what would happen if Brian continued to preach repentance to his local congregation. What if Brian lived in an area with a high concentration of LDS people? How would Brian's kids do in school?
Yeah, it shouldn't be too hard to relate to Lehi's experience. Want to amp it up a bit. What if Lehi had been specific in his calls to repentance? What if he named names. If he noted that the Sunday School teacher lived and immodest lifestyle. What if he called out Andrew's exceeding pride? Oh, how we'd get rid of Lehi.