I understand why they are playing him. I agree he still has .770+ potential, and in this league, that's 50 points above average. It could just be rust, but why wasn't he DHing with WOO all summer? We still have never gotten an answer to that mystery.
We are in the race, now. There can be no pulling punches. I've listed all of the long stretches of slumps Cora has allowed to continue, this year. Some, such as Story's and Rafaela's have paid off. (Maybe Wong will be the 3rd example as he has begun showing life, after a long death-like stretch.)
With Abreu out, the pressure on playing all 4 OF'ers was lifted, and the need to play Rafaela at 2B further lessened the bottleneck, but when Abreu returns, I don't care if Yoshida hits .770 or even .800: there is no place for him in the starting line-up, even versus RHPs.
I guess one could argue for playing Rafaela at 2B FT, so Anthony, Duran & Abreu-Refsnyder can all play everyday, but I have to think that weakening of our defense is counter to putting our best team on the field and in the line-up. I'd rather DH an OF'er- mostly Duran, and play DHam-Romy at 2B than keep Yoshida at DH.
If that means DFA'ing him, okay, but I'd keep him in the system at Woo for the reasons you mentioned. If he can ever get back to .770+, he could have value in 2026. Let him prove it in Woo, first. We can't afford to rehab him on the big club during a pennant chase. Plus, he can play FT at Woo and not platoon.