Two problems with your points about Gackle and Sharks defense. First, Gackle has far more access to Sharks, players, and other media analyst than both of us combined. Probably to the square-root as well.
Second, the Sharks are ranked #2 in the league on allowing the fewest shots against per game. And they're only 1/10 of a point from the #1 ranked stingiest defense. But they drop to #20 for goals against per game. So to blame it all on the defense doesn't seem to hold much water. It's a combination of both, not good goaltending and defensive lapses.
First, Gackle having access only means something if he actually has credibility behind anything he says and given that his track record with player acquisitions is abysmal, I don't see why you're mindlessly appealing to access authority here. It's just so damn lazy on your part.
Second, the Sharks are 8th in the league in most high-danger shots allowed five on five and 7th at even strength in general. I care about that since that's how most of the goals in the league are scored. That is the case because the team cheats and cheats a lot. More often than not it works for them to create dangerous offense but the drawback is that they allow a lot of dangerous shots to their goalies. I've never thought Jones to be a top-ten goalie in the league or elite by any measure. He's an average level starter but they're allowing too much in too dangerous of areas for them to handle. Shot suppression, if anything, hurts goalies when what they will mostly see is dangerous opportunities against them.
There are two major issues with this team. They cheat too much and try to get cute when they have the puck a lot of the times and their system is set up in a manner to where they generate the bulk of their offense from the point and if they turn it over, it's a dangerous chance against and there are only so many times a goalie is going to bail them out on those occasions especially if they're not seeing a lot of rubber to begin with.
I think they need to stop pinching so hard down the halfwall and they need to have the d-men shoot the puck along the boards if the shot isn't there instead of forcing it so much. And if they're going to pinch hard then the forwards need to commit to covering for them. I think that particular part has been improving since about Thanksgiving but you can't defend against point shots being blocked and turned over.