Their energy estimates are way off. 240wh/4gb download is too high by 100x.
It's not clear that there is a privacy argument. That address bar content is sent to google was always the case.
There is a bloatware argument especially if the only added functionality is form-fill which was done fairly satisfactorily without the 4gb download.
OTOH, gemini nano is now effectively open weight model if it, and it is likely a hack will permit user access to the bloat tax.