Google is/was in a somewhat special situation that they could show you ads that were relevant to what you are looking for. In 95% of the websites I visit this is simply not true.
As usual just because Google uses it and seems to be successful with it doesn't mean that it will work for normal companies as well.
ChatGPT in theory has the potential to show relevant ads as there service involves the user stating what they want. So they could actually present relevant ads. We'll have to see how it turns out.
I struggle to understand people getting butt hurt about a free service showing its users adverts, that will keep the service free.
They should have done this earlier, so their adds would be better by now, and they have a better chance against Google.