Is death inevitable?
This is a question which most people would still answer in the affirmative - so not much has changed since the Middle Ages (except the religious reasons given then).
The proper answer is 'no'. (It's also not inevitable that the Sun will rise tomorrow.)
There will always be the possibility an 'accident', but the chance of this happening on any particular day can be reduced to a very small level, and, if you survive that day, you have gained a day of life.
We may be able to cure all diseases one day.
We may be able to prevent ageing one day.
I don't suppose that anyone alive today will live to see either of the above two conditions, so we can say that death is inevitable for us, but not that death itself is inevitable.