I'd be happy ordering with a voice assistant if it's at least as good as I am at deciding good alternatives. Imagine I want to, say, purchase garbage bags, because I am out. It's not exactly a complicated product, and yet I might care about whether it has any smell reduction agents, whether the bag is tough enough, the size, and possible alternatives that are either a bit better, or quite a bit cheaper. Either the agent understands my preferences, or I am not going to trust it.

And as we look at Amazon's webpage, we first have straight out ads, then a few items it hopes I might buy that are typically related to what other people buy, and maybe a mention of what I bought before, but no understanding of why I bought that one. It's not a very easy task, and one where it's easy to lose trust