Is it possible some didn't? It was politically and economically useful to underplay or even ignore the risk from Covid. Once started on this path, governments at any level had to undercount and ignore to avoid being so screwed up that the mob would see. Even with the most level, honest approach it was impossible during some of the Covid time to know how many people had it, how many died from vs. with it, etc.
I suppose that some didn't underreport the death toll. To address your concern, I'm fairly confident that with proper application of statistics that a rough figure of deaths can be attained for different areas within a margin of error and compared with official numbers. I couldn't do it, but I'm sure others could estimate such a death toll from excess mortality figures and the like. Then again, you get into the issue of semantics and whether COVID was a secondary or primary cause of death and so on.