Not all the economic recession is attributable to the lockdowns. Some are attributable to global economy and supply chain issues.

And not all the deaths from COVID-19 are counted. Some of other excess mortality will also be due to COVID-19.

And the lockdowns had more benefits than reducing COVID-19 deaths. Eliminating influenza transmission alone reduced mortality by several percent: The difference between the officially reported COVID-19 deaths and the excess deaths may correspond to the number of deaths typically caused by influenza and other infectious respiratory diseases in winter months. This difference (computed starting from week 40 of 2020 and until week 15 of 2021), as a fraction of baseline annual deaths, was in the 2.3–5.9% range (Austria: 2.3%, Belgium: 5.9%, France: 4.3%, Germany: 3.9%, Slovenia: 3.5%, Sweden: 5.5%).

I mean it's an interesting paper, but the 10 times figure isn't supported by other sources.