He's not getting younger, either, but DH'ing mostly could help.
I think adjusting to the new culture and game could offer reason to think he could do better, but I just don't see how we can expect any better than what he gave us in 2023-2024, but maybe at more PAs.
He does have a 3.2 bWAR, career, which does come to about a 2.0 for 650 PAs.
fWAR really slams DHs. He has a career 111 OPS+ which is a plus for a DH, but not great. He has value, but just falls way short of the $18M a year he gets.
I think we hold onto him, until he gets healthy and a top prospect is busting down the door. None of our top prospects need to be added to the 40, and they won't be added until they are going to the 26 as a FT or very near FT player. There simply is not enough slots in the line-up for 4, right now. Even 3 is pushing it, and the catcher position might be the one slot, where our top prospect, Teel, is the least ML ready of the top 4-5 prospects at AAA (including Meidroth.)
To me, if Campbell, Mayer and Anthony are on the 26, Yoshida and Abreu will be traded, and whoever is playing 2B will be utility. Even this configuration squeezes the middle IF or moves Campbell to the OF or DH (3B, if we move Devers to 1B and Casas to DH, as I would like.)
This would be my ideal alignment (with Abreu traded):
C: Jansen or Higgy/Wong (Teel in '26)
1B: Devers (Casas back-up)
2B: Mayer (until Story moves here)
SS: Story
3B: Campbell (Devers back-up)
LF: Duran/Ref
CF: Rafaela/Duran
RF: Anthony
DH: Casas (Ref back-up)
Utility: Grissom, DHam, Wong, (Ref or Rafaela, whoever is not starting)