You have to look at the excess deaths figures. That is, how many usually dies from January to June in a normal year and compare that to how many extra that died in 2020. For Sweden the excess deaths almost exactly matches the number of Covid deaths, give or take 10%. That is not the case for many other countries. For example, the UK had almost twice the number of excess deaths as Covid deaths in a few weeks in April.…
Extra deaths don't have to come from underreported covid deaths. For example suicides and untreated medical conditions during social distancing and lockdowns can increase the number of deaths.
there's obviously some margin of error, but it's pretty safe to treat the unattributed excess deaths as being caused by covid-19