I hate that they are laying people off. I do however want to use some machine learning powered adblock, for those harder to block ads. otherwise I don't feel like every app needs an AI assistant. It's bad for the Internet generally and for the power grid.
In practice, it will most likely need to send the contents of your browser to some third-party server. No, thanks.
(Unless it's crowdsourced, like the first person to visit a page gets dinged, but then the next persons just downloads the set of rules instead of uploading content.)
Privacy preserving federated learning is a thing - essentially you train a local model and send the weight updates back to Google rather than the data itself....but also it's early days so who knows what vulnerabilities may exist