I get the point of view that many hold that agrees with this, and I can't reiterate enough how I don't really care if I'm wrong or right here, but two devil's advocate points:
1. Grier has cycled through a bunch of reclamation projects/young unknowns who haven't been given a full chance and has been happy to let a bunch of them go for assets that ended up being "selling high" or at least no major penalty to the sharks. Two of them (Eyssimont, Hill) ended up outperforming elsewhere but that doesn't mean he should have held on for longer on those players, or any of the others. Yes, yes, maybe he has misjudged the three players that anyone could see had more potential, but maybe not. Maybe holding on would have led to holding on to Addison, Zadina, or everyone's latest punching bag Kostin. Or he did hold on to Zetterlund - maybe that's the level of player he really wants to hold on to, maybe he said no to people who asked about him. We just don't know that Grier is systematically under valuing young assets just because he moved two (or three) that ended up rebounding/excelling elsewhere.
2. people keep saying this about Ceci but the metrics from the regular season and the ice time and results from the playoffs just don't fully agree that he's "objectively a bad NHL defenseman by virtutally any real metric that isn't an appeal to authority." For example the Athletic underlying stats model. Where are others getting their stats? Yes, the stats have team effects that may hide his warts, and Emberson's limited underlying stats looked better, but it seems like as a second or third pairing D he was able to be a neutral impact defenseman on the oil as long as he wasn't paired with Nurse. Again, I don't really care and I don't expect him to save our team, I would have preferred to keep Emberson, but I'm also not sure why everyone is so convinced Ceci is terrible versus just being a plug, and those two things are very different to me. Not every third pairing D in the NHL is objectively bad by any metric, they're just 2nd/third pairing D. Just like Ferraro is not an objectively bad defenseman - he's objectively bad as a first pairing defenseman and may be sliding into arguably bad as a second pairing defenseman, but he's an NHL defenseman.