>>48585535I assume it's probably due to SM more than anything, SM banked hard on being the 20th Anniversary game which wouldn't have worked that well for Pokemon Z (even though Kalos' dex is more encompassing of the whole series), plus if they released a Pokemon Z in 2015 instead it'd probably burn out people, I mean they'd still do SM regardless which means from 2012-2016 you'd get five mainline games back to back and probably a sixth given how little USUM did to change things.
The only alternative I can see is having Pokemon Z be in place of ORAS which seems unlikely since the prior third versions (E, Pt and B2W2) all had a year of downtime between the original releases and the updated releases so you'd probably have to cut ORAS and release Z in 2015 instead. However people would still be expecting ORAS which means you'd probably be looking at 2016 or 2017 getting double stacked with ORAS and either SM or USUM which causes that oversaturation problem again.
