I find Cursor's tab completion to be distracting enough with multi-line changes that I just disabled it, while I use IntelliJ's tab completion regularly.
Cursor's tab completion is better, but it doesn't seem to have a concept of not trying to tab complete. IntelliJ is correct half the time for completing the rest of the line and only suggests when it is somewhat confident in its answer.
I agree about the multi-line blocks Cursor proposes. Like it gets the first two lines right and then after that it's nonsense. I'd rather it stuck with a single line change at a time, and let me press enter before it predicts again.