Well, I don't think it's necessarily so black-and-white for the Cubs. I'll admit up front that I'm not really on Team "Sign Bregman to 5+ years", but I'm going to try to look beyond my biases and figure out a Cubs' line of thinking here:
Alex Bregman posted a 125 wRC+ at 3b last year at the 3b position which, league wide, was a 93 wRC+. It's a trash position offensively right now (it's behind catcher). We aren't seeing a decline in bat speed yet and he's been a consistently productive hitter with a plus-plus approach at the plate. Defensively he remains +. We know the team kind of struggled against LHP and he had a 139 wRC+ against them last year. You have Bregman, Shaw, Hoerner and Swanson who can all move around the lineup a little, giving each other some days off, maybe Shaw or Bregman can play some DH against LHH while you sit Caissie/Ballesteros (whichever you roll with).
When it comes to 2027. you let Nico walk and you gift the position to Shaw. Shaw, right now, looks not too far off from Hoerner, if we're being honest with ourselves. He was a near plus-plus defender at 3b according to DRS, and a move to 2b you'd think he'd maintain a very plus defensive rating. His wRC+ after his return in May was 99. Compare that to Hoerner's last three years: he's a 105 wRC+. Assuming Shaw shows progress, they're probably not that far from each other. That's no shade on Hoerner either, I like him a lot! But if you needed to find a Hoerner replacement...
That's probably your argument. You hope in this scenario that the Cubs have more money than expected and can sign Bregman, don't need to move off Hoerner immediately, and can still get a Michael King and improve the rotation.