Assumption is doing a whole lot of heavy lifting here.What's the reason they shouldn't run a $250-300M payroll? The first CBT threshold will be $241M in 2025, and the tax penalties for exceeding it are much less cumbersome if there's an international draft. There's no salary cap, and no points for surplus value or employing economic reasoning for the sake of it.
Wherever he goes is likely up to Soto. No team is going to give up the moon for him unless there's some understanding of extension parameters. There's no reason David Ortiz couldn't facilitate that discussion, if he hasn't already.
Say the Sox trade Yorke, Houck, Duran, Dalbec, Bello and Verdugo to the Nats for Soto and Corbin. Extend Devers at 10/$300M and Soto at 14/$500M. Here's the team in 2024:
C - Hernandez, Wong
1B - Casas
2B - Story
SS - Downs
3B - Devers
LF - Soto
CF - Rafaela/Jimenez
RF - Cordero
DH - Binelas
Bench options: Arroyo, McDonough, Jordan, Bleis, Hamilton, Bonaci
SP: Sale, Paxton, Pivetta, Whitlock, Gonzalez, Winckowski, Crawford, Groome, Seabold
RP: Schreiber, Davis, Ort, Walter, Murphy, German, Mata, Ward, Corbin
That team costs about $200M. I'm estimating arb figures for Pivetta, Cordero, Schreiber and Davis, and there'd be a question whether Soto's extension would cover his final arb years. Sale, Corbin, Pivetta and Cordero's contracts (about $60M) come off the books in 2025, when Mayer hopefully slots in at shortstop.
Soto is a "Top-25 hitter in the history of baseball" kind of player, to the best anyone can tell from here, and he's years away from his prime. If you're the Sox, you see if he wants to be here, and you make it work however possible. But I reject the idea that it would prevent them from fielding a competitive team.