The article seems to skip over the pandemic, which has changed behaviours significantly. Also, the Coronavirus itself is suspected to promote cancer [1].
It’s almost certainly much too early to have any data on the relationship between the pandemic and cancer. Cancer causing factors may take decades to turn into detectable cancers, and even if the data were available, publishing them can take a couple of years on top.
The study in question looks at data from before the pandemic: "Global trends in incidence, death, burden and risk factors of early-onset cancer from 1990 to 2019"
https://www.nature.com/articles/s41423-021-00750-4