Robotic toes.

Almost every Transformer has some kind of robotic organic part on them somewhere; fingers, noses, mouthes, facial "hair,"
head hair, teeth etc. Didn't necessarily make them organic per se. The thing with Transmetals was, as you said before, the beast modes looked robotic, but the robot modes looked organic - and it went far beyond just having fingers and toes. Half the Bayverse Transformers have toes (including Optimus Prime, Megatron, Ironhide etc.) -- doesn't make them organic, does it? Toes (or at least some form of foot articulation) is actually something any upright standing bipedal being HAS to have in order to walk! Even Masterpiece Optimus Prime has foot articulation... I don't consider that toy to be organic though. But you compare OpOp's beast mode with say Ultra Optimus Primal or Air Attack Optimus Primal's beast modes -- they look much more organic because they have detailed sculpted fur, skin wrinkles and their nails/claws are sculpted to look more organic.