Another effect is that Google has already been targetted for a lot of abuse, with SEO, backlinks, etc.. ChatGPT did not yet have many successful attempts at manipulating the essence of the mechanism to advertise by third parties.
Finally, ChatGPT is designed to parasite off of the Web/Google, it shows the important information without the organic ads. If a law firm puts out information on the law and real estate regulations, Google shows the info, but also the whole website for the law firm and the logo and motto and navbar with other info and Call To Actions. ChatGPT cuts all that out.
So while I don't deny that there is a technological advancement, there is a major component to quality here that is just based of n+1 white-label parasitism.