Just as life requires a complex interaction of interlocked systems death involves a complex failure of same systems. So ‘cause of death’ is already a simplification on that basis.
The intensity of simplification gets greater the closer you get to the event horizon and then after that can be influenced by legal factors, family wishes, time, coroner knowledge, media attention, if anyone gives a fuck.
Just as there’s a ‘hierarchy of death’ in terms of attention there’s also a ‘hierarchy of causes of death’ where we could analyse the social impact on our understanding of biology, fears about dying etc and how they feed into the causal lines we draw
It may follow that the intensity of simplification is greater under extreme stress, and there’s probably a bias with new things that kill that aren’t understood well
Does this mean a conspiracy? No
Does this mean the virus doesn’t kill healthy people? No
Does this mean COVID played a biologically significant role in all recorded COVID deaths? No
Mortality stats are already hazy and get hazier with a new very infectious and occasionally deadly virus with a massive range of symptoms