>>48165877In my opinion GameFreak doesn't really care much about the timeline anymore and created Mega Timeline so they could retcon the established timeline without explicitly retconning it.
That is why Toshinobu Matsumiya deleted the timeline that he had initially posted. The timeline that he had posted was applicable to Gen 1-5 and is also occasionally referenced in those games (e.g. the Red Gyarados broadcast at the start of DP which was later removed from Platinum).
It is not applicable to the Mega Timeline (Gen 6 and 7). Sina and Dexio give you keystones after becoming the Alola Champion, so I assume that SMUSUM fall into the Mega Timeline.
They needed to create a separate timeline in order to make ORAS roughly contemporaneous with X and Y. This would simplify the game mechanics and allow them to lazily copy-paste the Battle Maison into Hoenn (if ORAS and XY weren't roughly contemporaneous then the Chatelaines should be older in X and Y).
At that point they could no longer stick to a single timeline without contradicting themselves. Why? In XY there is a Breeder in the Magenta Plaza Pokemon Center who says that Team Plasma made news a while back in the Unova region. So XY must take place after the events of BW and BW2.
On the other hand, Black and White 2 replace the former Team Rocket Grunt "Bye-Bye a Go-Go" from GSC/HGSS Kanto who lived with his family in Iccirus City (in BW) with a former Team Aqua and Team Magma Grunt. Furthermore, there is a backpacker at the Desert Resort in BW2 who mentions that the Mirage Tower recently disappeared, suggesting that the events of BW2 take place after the events of Emerald. No matter which way you look at it Gen III takes place before Gen V and Gen V takes place before Gen VI.
GameFreak probably decided that the best solution is simply to create an alternate timeline. In this Mega Timeline the events of Gen "III" are not necessarily contemporaneous with Gen "I".
