I don't remember specific examples but the answer is formulas. Google Sheets lacks a lot of the "advanced" non-math formulas.

So is it just the UI or the actual functionality? I know the deep deep functionality probably isn't there but I want to know how deep you have to go.

You can also change the UI to have the ribbon. It doesn't do it by default because I think they're worried about legality.

Also the qt theme on wayland lags like hell and is completely unusable. It also didn't scale well either.

Okay. I solved that by not using office at all.