The Leafs inability to draft and develop a starting goalie is a MASSIVE organizational weakness. How many picks, prospects, etcs have we thrown out the window trying to trade our way out of this problem? Seems every couple of years we're trading away a prospect + 2nd, a 1st rounder, etc for a goalie, and most of those trades have been flops.
In terms of trading for Gibson - it's obviously risky, given the contract and poor stats for three straight years. Yes, people are finding ways to explain those stats (e.g. starts against quality opponents, high danger save %, etc), but at the end of the day, he's had bad stats for three straight years, whereas goalies on other bad teams (and even his own team in Stolarz) are able to put up better stats while also playing for a bad team. So could he massively rebound if put in a different situation? Sure, potentially, but he could also become an anchor contract if he's anything less than a bona fide top 5-10 starter.
If we do trade for him, Anaheim would clearly be in full rebuild mode. I don't think they'd have interest in Nylander with only 2 years left on his deal. I think they'd be wanting Sandin+, Robertson++, or something along those lines. Which I'd be open to, as long as we were quite confident we were getting a bona fide top 5-10 starter.