I'll use your argument: just because you don't want as many platoons that the Sox have used, very successfully I might add, doesn't mean it was the wrong move.
BTW, this point I made is moving away from a platoon.
Also, I don't want Romy as our FT 2Bman. I just said, I could see the bean counters justifying not adding someone to the 2B mix, because the stats and metrics show maybe Romy can do it just well enough FT.
One more point, Casas got hurt in early May, Devers was traded in early June. Romy started playing near FT in mid July, mostly because he was hitting very well and was doing well even vs RHPs. (He kinda dropped off at the end.) They tried several players before Romy and added Lowe in August, which meant no Romy at 1B vs RHPs. Romy started playing 2B vs RHPs, because DHam sucked, not because of Casas. Yes, had Mayer stayed healthy, he may not have gotten a long look, but if Bregman bolts, we may see Mayer at 3B not 2B, so we're back to the same hole at 2B.