If they had no plans to give him a chance to redeem himself, even when the team is struggling defensively like they are now, it was a mistake.
There was an avenue available to remove him from the roster with no dead cap space that would have saved a small amount of cap space this year too. For whatever reason, Nonis chose not to use it and the result of that decision could be another 3 years of close to 3M in dead cap space.
If he is a bad fit and a bad contract then it was a mistake by the GM that didn't compliance buy him out or the GM that gave the player the contract in the first place?
Where does accountability lie with the GM that made the mistake or the GM that hasn't corrected it yet? What happens if Nonis deals him away in the future? There is a Liles for Gleason rumour floating around.
However now that he wasn't bought out, suddenly its a coaches mistake for not playing a player considered worthy of being gone via buyout, which would have made him unavailable as an option today. So is Liles now considered better than what Leafs currently have playing for them, and wouldn't that validate not buying him out for those that want him in the line-up?
Wanting him bought out and wanting him playing for the Leafs seems like a major contradiction in beliefs of player value to me.