I know it's just an anecdote, but my biggest problem with Google's Bard/Gemini is that the moment I tried to ask a question about something - I started getting ads all over the internet and social media related to that.
Doing this with ChatGPT 4.0 for months and months did not cause this type of behavior.
Doing this with ChatGPT 4.0 for months and months did not cause this type of behavior.