Singapore does a great job of testing and the vaccination rate is >95% for the eligible population. Despite that, they have introduced restrictions due to ICU overload.
Look at "Proportion (%) of cases ever critically ill in ICU or died, by age and vaccination status"
Looking at the high risk group of 80+ year old (43% of all ICU cases and/or deaths), the numbers are: unvaccinated (24%), partially vaccinated (16%) and fully vaccinated (3.2%).
They don't define partially vaccinated (typically 14 days after 2nd dose). So clearly the vaccine reduces the risk of ICU/death, but the "truly" unvaccinated make up only 50% of ICU cases in that age group.
From all the local reporting the overwhelming majority of people in Czech ICU are not vaccinated. A few examples - listing from a hard-case ICU in Ostrava for a week in November:
The last 5 patients are those that have been released from the unit in that week.
The first two were move to less severe case ICU. The last three died...