SAN JOSE, Calif. — This trade deadline could have been a hard pivot toward the future for the Islanders.

Instead, it ended up as something in between, not quite the same old standby of defiantly sticking with the group, but not quite enough to call this deadline the full-blown retool it could have been.

Moving Brock Nelson on Thursday night for a package headlined by a future first-round pick and prospect Calum Ritchie was a seismic move for the Islanders, one that bolstered their asset pool and maximized the return for a player who, by all indications, wants to test the market upon hitting free agency July 1.

Declining to move Kyle Palmieri on Friday, with the Islanders instead agreeing with the player’s camp to keep working on an extension — though nothing is done yet, a league source indicated that the sides are close enough that both believe something will happen — sends the opposite message, and gives off a feeling that general manager Lou Lamoriello only moved Nelson because he was backed into a corner.

“I want to be here,” Palmieri said, confirming that his agent is talking with Lamoriello. “And I want to be fighting for a playoff spot with these guys. … The last couple days of waiting and hanging out here were tough, but I’m focused and excited on the opportunity this group has.”

As for other assets the Isles could have dealt, namely Jean-Gabriel Pageau, Anders Lee and any one of their surplus of defensemen, well, stripping this team down to its foundations just wasn’t in Lamoriello’s DNA, even if this season provided a much more compelling case to do so than anything in recent memory.

The Islanders have watched Anthony Beauvillier, Josh Bailey and Cal Clutterbuck — all staples of the dressing room — walk out the door in recent years.

But losing Nelson, an alternate captain who is still performing at a level high enough to be a part of Team USA last month and who spent all 12 of his NHL seasons with the Islanders, feels different, because it is different.

Beauvillier was part of a deal that got the Isles Bo Horvat, and has since drifted through five different organizations, the latest being a trade to the Capitals on Friday.

Bailey and Clutterbuck have not officially retired, but for all intents and purposes finished their careers on Long Island.

Trading Nelson for this package was as necessary a move as it gets.

Still, it was an acknowledgment — however begrudging — that continuing to push all the chips in on the present was not viable.

For the first time in a long time, you can look at the Islanders and see the makings of a strong team in 2028 instead of one fighting a battle against time in 2025.

Ritchie is a blue-chip prospect, Cole Eiserman could be as well, and there is hope Quinn Finley and Danny Nelson turn into solid NHLers.

Horvat, Mat Barzal, Noah Dobson, Alexander Romanov and Ilya Sorokin will likely be staples here for a long time to come.

The other side of that, unavoidably, meant blowing a hole in the current team and in the dressing room, where no one is giving up on making the playoffs, but the roster is worse now than it was two days ago.

Lamoriello elected to make this transition in slow motion instead of all at once, but if it wasn’t quite the end of an era, it was the beginning of the end.

“We wish there was something that could have worked out [with Nelson], but at the end of the day, it’s a business that we’re in. They had to make a decision on which way they were heading,” Casey Cizikas told The Post after Friday’s practice. “End of an era … there’s still a few of us left here.

“… He’s been here so long. But over the years we’ve lost guys that have been here between Bails, between Clutter, those guys were here for a long time. They were an identity of our team for a long time. It is what it is when it comes to hockey. We’re not getting any younger.

“We’re fortunate. You don’t really see that too often in this league. You could probably pick out 10 guys that have been together for 10-plus years. That doesn’t happen. That’s extremely rare. Extremely thankful for the time that we got to spend together, but these days are never easy.”