I mean seriously. This guy sucked at his job. He just randomly went in to world leaders in the middle of political meatings and rambled something about the end of the world, without any mention of who he is, how he know or at least, what exacly is to come.
One would think at least with a guy like Antonidas, he would have mentioned the Burning Legion, the Wardens of Tirisfal or the Tirisgarde. Surely, beeing the leader of the Six, a few bells would have rung in Antonidas head. But no, just “This land is doomed guys, ok? Lets have a Mass Exodus into the unknown. Trust me, mhkay?”
Actually makes you wonder why Thrall and Jaina listend, with next to no information on the matter given.
Anyways, do you think the reaction of people like Antonidas or Terenas would be different if Medivh actually did tell them about what was to come? (Maybe not outright stating he is the Warden, for he was a Traitor in the First War, but at least hinting at something in that generals direction)
Well Thrall listened cause he communed with the elements and they told him to trust the stranger, as they felt that he had no harmful intentions or any kind of malice.
Jaina listened much later, after the entire kingdom of Lordaeron was razed by Arthas and the Undead, with Antonidas bidding her farewell as he realized Medivh was right. So Jaina didnt exactly listen, but more like confirmed that this land is doomed.
Thrall and Jaina listened because they had nowhere else to go. Thrall was looking for a new place to settle and when Jaina left Lordaeron was already in ruins. Terenas and Antonidas were warned when their kingdoms still prospered. Medivh was a fool to think they’d be willing to leave a land they inhabited for thousands of years based on the ramblings of a so-called prophet. Plus he had no proof that he was telling the truth or that he was to be believed.
Seeing Medivh was slain for being the Demon-corrupted magus who initiated the Orcish invasion of Azeroth, presenting himself as his true identity for which he was executed, might have caused an even worse reaction on the side of the Alliance than being dismissed as a doddering fool.