Did you read the article? The point of the study was that covid has had no affect on the overall number of deaths. This is in contrast to most publications which cite at least 250,000 deaths.
Of course a one off non-peer reviewed piece isn't proof of anything but it does reference interesting data.
Heart disease, influenza, and pneumonia really are things that kill every year, so why don't you think they can be statistically analyzed? This year is different than previous years, but it seems odd if you're suggesting Covid is beneficial for heart disease.