It is still useful to be able to answer "What was your chance of dying of covid compared to all other types of deaths based on your vaccination status". Becaus

It is still useful to be able to answer "What was your chance of dying of covid compared to all other types of deaths based on your vaccination status". Because if you can't do that you can compare data even with the status and vaccination rates changing over time. So even if we lump together all different cases at different times saying that person in this class of people had less than 1% of chance of dying to covid vs. another class where you had 30% of chance of dying to covid is a clear indication that one class was much more resistant to dying than other.