Soto? He's missed the entire year and is a HS kid still at this point.
They aren't putting all the rest of the starters in the bullpen, you need 2-3 in waiting. Plus, they see more value of starters so they'll wait to convert others.
Go look at the free agent list, and ask yourself who they would sign. They aren't signing a CF, 3b, SS, 2b. What corner OF that is good will sign for one year, given they have five or six OF in the majors, AAA and AA? That leaves first and catcher.......