healthy people with no underlying conditions do die from covid.
its about viral load.
if your gathering near a sick person for long periods to inhale large amounts of the virus. more then even a healthy persons immune system can battle. you will die from it.

but the other thing is the long covid. where people dont get to 100% normal again after a few days but stuck with an illness for months.

anyway
many healthy/fit doctors and nurses have died and many more have got long covid purely because of viral load.

the UK done a study earlier in the year
heres the summary
Of the 33,841 deaths that occurred in March and April 2020 involving COVID-19 in England and Wales, 30,577 (90.4%) had at least one pre-existing condition, while 3,264 (9.6%) had none.

9.6%
ill emphasise this 9.6% had no underlying condition

yep 3k died thinking that covid cant hurt them because they have no conditions.
3k out of 33k

the number is not 0%. its 9%
just take a few moments to realise this fact and realise the risk is not zero