Welcome to the DS era. Nintendo said goodbye to single screen gameplay and hello to dual screens (again) and ushered in Generation IV with 3 new games (and 2 remakes). Pokémon Diamond & Pearl notably brought back the day-night system and introduced a crucial competitive mechanic: the physical/special split. The games were influential for a lot of popular content creators, despite them being so painfully slow.
Then Platinum enhance things and made it slightly faster. Gen 4 was not my favourite but I did love the Gen 2 remakes. And some of the new evolutions.
As for the commercials, they dropped the kids and went for build up, the dragons, and gameplay footage. And for Platinum, cute Pokémon running around, more footage, and then Giratina swooping in for 2 seconds. I hope the kids come back soon.