>>58775349It's a stretch to call Gen 4 an anniversary celebration or Kanto pandering. The 10th anniversary was hardly a thing. There was the American "Journey" event, the Pokemon X CD, and the Indigo League DVD sets.
2016 was a different beast. It was the first time there was a big marketing push. A lot of that was riding the momentum from X/Y, even though 2014-2015 revenue had flatlined. The success of Pokemon Go lead to this weird situation where the 20th celebration bled over into 2017-2018 to capitalize on that Pokemania 2.0.
The 30th is coming after 10+ years of the Kanto machine and the nostalgia machine running at full speed. They don't need the mainline games to push Kanto stuff like they did in 2013 or 2016, and unlike 2016, there are multiple generations of adult fans who grew up with later games. There are adult fans who started with RSE or XY or SM. Z-A is probably a good indication of how they'll celebrate the 30th, with a wider range of new forms and evolutions across all gens.
Obviously we'll get Kanto stuff, like the Pikachu redesign, but not at the expense of other stuff. This is an island hopping adventure, and it's the 10th anniversary of Sun and Moon, so I expect we'll see lots of Alola pandering too.