Yes and No.
I think it goes beyond "hope" when expecting younger players to improve as they gain experience. I think it's an expectation for most to improve, and plan on a few not to improve.
I don't think we are a half a team away from being serious contenders, even if you look at just the 26 man roster (13 players needed?) or the starting lineup + 5 SP'ers and 4 RP'ers (9 out of 18?)
It all starts with Bregman's return or not, but if he bolts, and we spend $40M elsewhere, the theory is we should be able to fill his line-up slot or two with that money.
Of course, players like Rafaela, Narvaez, Abreu and the 3 kids could regress, next year, but many could improve my major amounts to offset those declines, and then some. Plus, we could see Casas back, Duran peak again, Story hit .750 and the Ref, Romy, Toro brigade continue as is.
We lose a lot of pitchers, but we also lose their money off the budget, too, including wasted money like Hendriks, and money we spent this year with next year in mind, like Sandoval. There are some positive ways at looking at this, if you choose to do so. Yes, it's not about just spending more: it's also about spending wisely, and that may be a bigger ask than asking JH to spend even equal to 2025's over the tax line amount.
If we keep the budget the same, we will have an insane winter spending budget, especially if we go by AAV/Tax dollars and do some creative financing with contracts, like the Dodgers have mastered. We have some major pieces we can afford to trade away, due to near equal depth at like positions. Not many teams have the packages we can offer in trade, without opening a new gaping hole at another position. This doesn't mean we have to trade Duran and Abreu and pin all our hopes on 3-4 kids in the OF (Anthony, Rafaela, Garcia & Campbell,) but I would not view that as needing wildly unrealistic hopes in our youth, especially if Refsnyder returns and maybe Yoshida plays some LF at Fenway, only.
We have a pretty deep foundation, even though many are young, too young or looking too close to mediocre to get excited about, but it's more than half a team. IMO, if we go big, we could be serious contenders with 4 additions assuming Bregman returns (SP2, Closer, 1B and 2B) or 5 without Bregman.
I think the rest of the team can be good enough support of these added 4 to 5.