Mets first baseman Pete Alonso walks to the dugout after...

Mets first baseman Pete Alonso walks to the dugout after striking out in eighth inning in Game 6 of the NLCS against the Dodgers at Dodger Stadium in Los Angeles on Oct. 20. Credit: Newsday/Thomas A. Ferrara

There were two prevalent reactions when news broke early Monday morning that the Mets had agreed to bring back Sean Manaea on a three-year, $75 million deal.

The first was joy. Manaea, who’ll turn 33 on Feb. 1, not only became the de facto ace of an unforgettable Mets team that unexpectedly made it to the NLCS but so often was its beating heart — affable, quirky and fiercely competitive in a way that made baseball particularly fun.

The second was impatience. While plenty of people clamored for Manaea’s return, he was only part of the magic that fans so desperately want back in 2025. Manaea is great. Juan Soto is really great. And even with all that, no one has forgotten about the true Son of Flushing.

Pete Alonso still is not a Met, and given that Monday was Festivus — the Seinfeld holiday known for its “airing of grievances” — let’s air one big ol’ grievance, shall we?

President of baseball operations David Stearns and owner Steve Cohen have done a masterful job this offseason, with one glaring omission: It’s time to bring Alonso home.

Look, there are plenty of valid reasons for the delay. Stearns is acutely pragmatic in his dealings, with an eye toward value, efficiency and optimization. And Alonso, for all his many strong attributes, is a risk.

Here we have a power-hitting first baseman who is 30 — the type of player who, historically, can tail off significantly as he approaches his mid-30s.

Alonso, who is represented by relentless agent Scott Boras, no doubt is looking for a lengthy contract, and the Mets already have committed to Soto for 15 years. Alonso’s contract also will be in the hundreds of millions of dollars — not exactly ideal when you’ve already spent a few seasons spitting in the eye of the competitive balance tax and are likely to keep doing so for some time to come while incurring all the pricey penalties that go with that.

Alonso hit just .240 last year with a 24.7% strikeout rate and isn’t all that fast. He did hit 34 home runs, plus the stunning three-run bomb against Brewers closer (and now Yankees closer) Devin Williams in the ninth inning of Game 3 of the Wild Card Series that saved the Mets from elimination.

Defensively, he’s below average, though his proficiency in scooping out errant throws saved the Mets a few times, particularly as Mark Vientos was getting his bearings at third base.

Are we done with the caveats now? Good. Because none of that should take precedence over the fact that Alonso belongs on this team, makes them better and has earned the opportunity afforded to homegrown talents such as Brandon Nimmo and Jeff McNeil: Play your cards right and stay a Met for life.

The bottom line is that baseball is a business and Alonso is good for business. Without the pressure of playing in a walk year and with another power bat in the lineup in Soto, Alonso will be put in a position to succeed.

And frankly, look at the other options: Christian Walker and Paul Goldschmidt are off the board. Do you want a 40-year-old Justin Turner? Or a 35-year-old Anthony Rizzo? Do you want to go after third baseman Alex Bregman and move Vientos to first after he’s already shown significant progress with his defense at the hot corner?

For what it’s worth, Bregman, though an elite fielder, isn’t an offensive upgrade over Alonso. Known for his ability to get on base, Bregman saw a significant dip in that regard last season, dropping to a .315 on-base percentage compared with a career .366 OBP.

Alonso’s weighted on-base average of .340 last season is actually nine points higher than Bregman’s (.331) and his wRC+ (weighted runs created plus) is 122 compared to Bregman’s 118. Alonso also played all 162 games last season to Bregman’s 145.

Of course, there’s more than that. We’re still people, after all, and fans have an emotional connection to Alonso. He’s earnest and sometimes a little goofy, and his love for the franchise comes out of his pores.

We often think of power hitters as imposing and unsparing, but Alonso, despite his size, is an imp — cradling a playoff pumpkin to every postseason game because he didn’t want anyone to mess with his special talisman.

When the Mets needed a leader, he was a leader, even if his playful personality doesn’t always seem particularly suited to the role. And when Francisco Lindor stepped up to become a vocal, if unofficial, captain, Alonso was just fine adjusting to a little bit of a different role.

Fans want him back. And he has a chance at a legacy here: getting the rare opportunity to spend his entire career with one franchise and potentially having his number retired.

He is, in temperament and personality, a Met to his core. It’s time to make it official.