This is going to sound REALLY flimsy, but this was something that suddenly occurred to me when watching JN102, and you're probably wondering "How is that relevant?", the answer being that episode was the last time Gary was shown to have a NEW pokemon in his possession since this episode, but that's neither here nor there as the other answer to that question lies within Gary's in-game counterpart. This episode was Electivire's debut in the series, this one being under Gary's ownership, but what's interesting is that Gary having an Electivire isn't as random as one would think. Yes, it served as a means for Gary to show off a new pokemon that he got from the region Ash literally just learned about, however, and this is the flimsy part, Gary's in-game counterpart, Blue uses an Electabuzz in Stadium, so in that regard, Gary having an Elecitivire isn't that farfetched, and it would take very specific set of mind cogs to turn to notice a VERY subtle nod to past games that the writers would not have been aware of.