I work in a hospital back during the last big peak in late Feb where beds were filling up, there were plenty of people who had been vaccinated who got sick but almost none who were in intensive care who had received vaccination. We never had more than one person in intensive care who had been fully vaccinated at a time and every single one of those had other factors like diabetes or obesity.
There were a lot of people who hadn't been vaccinated in intensive care with covid. (Despite 70% of people being vaccinated in this area).
It doesn't look like the vaccine prevented many people getting the virus but it sure as hell stopped people getting it as severely.