>>40398498It's because of the anime. Obviously Game Freak doesn't give a shit about the Porygon incident since they gave it 2 evolutions over the course of 10 years. However the main series and anime are still strongly tied together, so that would definitely put pressure on Game Freak not give Porygon something that would "force" Ash to use one (such as Pokedex integration).
Also I think Ishihara and other higher ups at TPC and Game Freak just really love Rotom. Consider
>it's based on Pulseman>4 type combinations are still unique to it>has more substantial (i.e. not purely aesthetic) forms than any Pokemon other than Arceus and Silvally>the Rotom forms are the only Pokemon to ever get a type retcon without implementing a new type>pic related 