The only argument is based on how the online functioned. For the actual games XY is extremely mediocre and ORAS is arguably a sidegrade to RS and worse than Emerald in almost every way that matters. If you get into spin offs the dearth of them puts it lower than the previous generations but still somehow more than most gens afterwards, quality or lack thereof for any of the titles notwithstanding (I liked Super Mystery Dungeon well enough).
>>57600261Gen 1 is just buggy enough in the exact right ways that there's a lot of interest to be gained from fucking around with that. If you're going off intended game design however, yeah it's not super great but I'd still probably replay it over some post-DS titles purely because the campaign is fairly breezy if you skip a lot of the drudgery found in the technically optional content. Being worse RS is better than being SS (which is just worse XY in every meaningful way), easily.