I agree, in a sense, and I was in the camp that Iafallo was overrated and a bottom 6 player, though I have changed my tune the last season or so to one who believes he could be a top 6, or at least a second-line player.
It is tough because if you look at just his stats, they are in line with everything he's done for the Kings thus far which goes to show just how hot he was to start the season and it starts to have the feeling like that pace was an outlier.
Trying to trade him now would come with huge red flags and we'd likely have to pay to take the contract off of our hands. There are no good options other than letting him play out another season to see if he re-discovers his game.
But right now, he is ineffective, beyond snake bitten, has lost all confidence, and looks like a 4th line placeholder that is just neutrally eating minutes for no reason. The rest of the "first" line suffers a bit from this as well, but not necessarily as much as Iafallo has. Though Kopitar deserves a mention as being close.