The honest answer is that they see AI interaction as being the next human to computer interface, one that will function much in the way that super-apps do today, with the benefit of accelerating the purchasing pathway.
In a way this mirrors how people opt for using apps even though a web version exists, because the apps are generally more performant.
I'd argue that ChatGPT is already there. The instant check out feature they've added, along with integrations was that crucial link between recommending and fulfilling a purchase. It turns ChatGPT into something that can very directly assist with typical "life stuff".
As examples: You're having a dinner party, it can set the menu, then buy the ingredients. At christmas, spend a few minutes talking about your kids and then it can make christmas gift suggestions and go and buy it for you, then do it again 12 months later.
Getting between the consumer and their purchases would be highly lucrative, it functionally replaces one of the core functions of advertising and retail.
What a nightmare!
Why would I want any of this?