Sigh. So understand, the King has led us well and wisely for a very long time, and we've grown to be the greatest of the peoples of Valinor, and while from what I know it sounds like there were some mistakes in how this situation has been managed, there's much I don't know.
The King has three sons. His eldest, Fëanâro, is by a different mother - she died, and she refused to come back, and the King's grief was very great and drove him to remarry, though perhaps it was unwise, and with his second wife he had two more sons, and two daughters.
And for a long time they all got along tolerably, I think, if not exceptionally well, but then - Yávië says that she heard that Nolofinwë, the King's second son, was saying that Fëanáro was ill-suited to rule and ought to step aside, and that if he didn't something ought to be done about it, and that's - well, it's terribly rude, and unwise to mention, but it could've been offered in the spirit of constructive criticism, right, or he could've favored Fëanáro eventually stepping aside in favor of Fëanáro's son, who is eminently suitable for the role. But somehow it got about that he was considering persuading Fëanáro to move out, instead, with his family, a proposal to which Fëanáro objected vehemently. And Fëanáro runs a guild of metalcrafters in the city and he set them to forging swords, and carrying them, gods know why, and so Nolofinwë did that too, and now it's a fashion in Tirion and everyone has those horrible swords and everyone is tracking who is in favor of who and spreading dreadfully stupid stories about one another.
And - the city has lots of fads, right, they went through a time where everyone went around with their eyes closed to expand the other senses, they had a raging fight about the shift in phonemes from th- to s-, one year they declared that it was a bad year for having babies because of something strange in the air from their workshops, and no one had a single child until the Valar'd been called in to fix it. It's going to be fine. everyone will apologize to each other and calm down. But I still think, in the spirit of constructive critique - swords are a silly tool to make this kind of point with, they're menacing. Someone could hurt themself accidentally.
He is sincere in all of this including his conviction that the likeliest way for harm to result is someone hurting themself accidentally. He is worried he's giving Leareth such a bad opinion of the King, who doesn't deserve it.