No, Yoshida should not be benched or platooned, unless something changes over a long period of time.
Turner is a proven vet who almost always does better in the second half. He was one of MLB's best 2nd half hitters, last year. I would look to bench him, either.
Duvall's start could certainly be a fluke, but he is not far removed from leading the league in RBIs. I could see him being partially platooned, if he comes back and struggles vs RHPs, but I don't expect that to happen.
The most likely platoon bats might be Duran and Casas, but both are LHBs.
Could Kike or Duvall be benched vs RHPs? I doubt it, but if Duran keeps hitting well, and Casas comes around, who knows.
I will usually defer to the vets, if all things look equal. One can't just go by who is hottest over the last 3, 4, 5 or ___ weeks..