I interpret this as you saying that we need saving from the eventual predations of the shopping AI agent industry on helpless consumers. Honest question, why won't competition come to the rescue? Any number of startups hungry for customers will be competing to provide the best version of the product that they can afford to provide, and will eventually settle into some fair equilibrium, absent the government picking some kind of winner or imposing binding price controls.
It's true that Uber used to offer outrageously good prices to acquire users, and nowadays charges what some people consider outrageously high prices ($80 to get me to the airport??). But a closer look at the economics of the situation reveals that the prices that rideshare services have settled on are the pretty-much-sane ones, accounting for the market value of the driver's time and uber's cost to develop and maintain the app. Why wouldn't the end result of the AI shopping agent market be the same?