You may think it's easy to calculate Covid's death rate, it is simply
(number of deaths due to Covid/number of Covid patients)
Indeed even a primary school student is able to say that, but what's difficult is in fact getting the numbers. Like any ratios, one can either attack the numerator or the denominator. Some questions to ask:
1) How to account for people who are actually positive but not diagnosed? Not to mention the there are some countries where a patient is not classified as positive if their viral load is below a specific percentage.
2) How to attribute a death to be caused by Covid? It is indeed a billion dollar question that many insurers want to answer.
Some journalist have adopted the excess deaths strategy. That is counting for the number of deaths in a covid year nett off the number of expected deaths due to (old age, critical illness, traffic accidents). Yes we can account for those things from an Actuarial perspective, and responsible governments take those trends into account in investing for hospital capacities.
But this excess death strategy has its issues too:
a) firstly, Actuarial estimates aren't perfect
b) secondly, how do we account for the change in deaths due to movement restrictions (less movement, less traffic accidents for example?)
So in my opinion, an expert isn't one who can calculate the formula above well. An expert is one who can make adjustments to the questions asked based on limited data in a logical and agreeable way. I rate agreeable as being able to replicate one's method and not losing the rigours of research.