I tried Gemini for gDrive to find some files and it was useless.

I tried it in Slides to generate some slides from text, it was useless.

I tried having it produce a plot for me in Sheets and it was useless. (It does look up documentation but I could already do that.)

I haven't found any useful feature for it in Google Workplace; but I do get AI summaries of everything now, which I don't need and have to keep dismissing.

I haven't yet used it in Google Docs -- it's probably decent there for writing.