Interestingly, the US is not one of those countries. If you tally up the excess deaths for the year (as per the public CDC data), they match C19 fatalities nearly exactly.
More starkly, visits to the ER for strokes and heart attacks plummeted during lockdown. But there weren’t actually fewer strokes and heart attacks. Many of those people just died at home.
In short, no one can say how many of excess deaths were COVID vs lockdown deaths, but it certainly isn’t the case that the “lockdown”‘category is actually a net negative.