>>51678687>>51678901TPC doesn't care about lore, only marketability.
If Iris and Lance fought each other, one of them would have won. TPC didn't want either of them to be in the finals since Johto and Unova are hated by most of the nu-fans who watch the anime. (Eevn tough Lance first appeared in Kanto most nu-fans are too stupid to know this and just see him as a representative of Johto's "terrible teams" due to his three Dragonite.
Also Iris and Lance aren't marketable enough to make it into the finals since they don't appeal to coomers due to Iris being a little kid and Lance being a man who isn't a "bara" or a "twink". They had to be sacrificed to marketable coomable waifu's like Cynthia and Diantha
's Gardevoir. 
