Keep in mind this is the incidence of cancer diagnoses. The quality of healthcare, diagnosis standards, and amount of preemptive screening varies heavily between countries.
Even in pretty terrible healthcare systems, I would expect that close to 99% of people dying from cancer will actually be diagnosed with cancer, even if done too late.
You might be able to claim that for some countries, but all European data should be reliable, all countries have reasonably good cause of death recording.
After listening to stories from my Canadian friends about how hard it is to just get basic medicine like antibiotics I'd expect this to be caused by a lack of screening/diagnosis rather than actual differences in cancer rates.
Do they live somewhere that requires a float plane to reach a doctor? I've never heard of a fellow Canadian having a hard time getting antibiotics, what a bizarre anecdote.
The 2020, 2021 dip looks fishy, I would hypothize this is related to the pandemic lockdowns and overburdened hospitals reducing the number of cancer diagnoses. But it's a hypothesis that would need to be confirmed with the relevant numbers.
It would be useful if the data differentiated by type of cancer. For instance, skin cancer diagnosis is straightforward and inexpensive. Visual identification and a biopsy, led by the patient noticing a difference. Contrast that with pancreatic cancer, which requires imaging for diagnosis.
As it is the only meaningful conclusion to draw from this data is that we need more data.
Japan, having ~the highest average age, should be on the top of the list but is not: second-highest bin. Australia is the skin cancer capital of the world ('Approximately 2 in 3 Australians will be diagnosed with skin cancer before the age of 70'), yet is in the third-highest bin. Isn't that interesting!