Exactly, and that's why you can't rebuild with him on the team. He's still good enough to prevent the Pens from being among the worst teams in the league. So let's say he plays 4 more years while the Pens rebuild and they collect picks in the 10-15 range. Once Crosby retires, the Pens are ready to bottom out. Except those picks are now starting to contribute and keep them from becoming Arizona, so they don't get a chance at a franchise-level player. But at the same time not good enough to lead the franchise to glory themselves. So the Penguins become the Flyers of the last decade.
It's not enough to just say you want to rebuild. You need a plan to build a championship-level team.
Sid alone isn't going to power the team to the playoffs. That's not how hockey works. McDavid and Draisaitl, two of the very best players on earth and in the peak of their primes, barely eeked the Oilers into the playoffs in a far less competitive Western conference. Sid's very good, but he's not 115-120pt good anymore. If this team was a buncha schlubs and Sid, they're absolutely drafting in the top-10 comfortably, maybe even top-5.
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Picks in the 10-15 range are out of the playoff picture, and if that's the case, just blow it up anyway because you can't even keep up the masquerade of being contenders. If this team continues to cruise along like they have been, they'll be a playoff team more likely than not. They won't have a snowball's chance in hell of competing for a Cup, but they'll make the playoffs.
That's purgatory. That sucks way worse than the team ripping off the band-aid and going full rebuild because they refuse to go and pull off the moves needed to reshape a roster that just can't get it done anymore. That's how the Red Wings turned a like 5 year rebuild into what's shaping up to be like a dozen year-long rebuild.
It'd be less shitty to watch a team full of nobodies and cap landfill guys to hit the cap floor collect potential franchise pillars through the draft than it would be to know this team's neither got a shot at the Cup anymore, nor collecting premiere prospects in an attempt to climb back to legitimate relevance. /shrug
Fwiw, I'd prefer Hextall start removing bloated contracts and legitimately making a run at guys who add enough offensive punch to make a difference, like Forsberg, or JT Miller. I don't think that's realistic though, he's just not gonna do that and ownership--for all their bullshit media-speak, doesn't seem interested in forcing him to do things like that. I fully expect several more years of increasingly boring, mediocre hockey until the guys hang up their skates and the team's hand is forced. And again, I think that sucks.
Also, please spare me the "Boy I can't wait for the Pens to draft the next Nolan Patrick" bullshit. You need the top-5 picks to have a way better shot at landing the Makars, Heiskanens, Huberdeaus, Barkovs, MacKinnons, etc. If you consistently botch those picks, and I'm definitely agreeing they're not all going to pan out, your scouting/drafting/development teams suck shit and need wholesale replacing. That's an organizational issue and not a "you can't hope to build through the draft" thing.