From what I noticed they only added an emoji button though. This already is on my keyboard area. Maybe I'm missing something but at least you enjoy it.
And the emoji button in the message area has less features than the one found in the Google keyboard (no emoji kitchen?!), so I'll never want to use it anyways.
There is also the new AI response button. But not everyone sees that. I think that's the biggest reason for this change. It looks better than the couple other ways they demoed the ai smart reply ui.