Some groups do put the figures above 1 million.[0]
> I think the estimates for Gaza, with a population of about 2.2 million, are between 70 to 75,000.
Keep in mind these figures are not civilian casualty figures, they are overall casualty figures.
Data quality issues do make comparisons rather tricky. Generally you would also want to compare against similar battles that have mainly urban conflict rather than a war in a large country where the amount of fighting varied much more.
In any case looking at raw casualty numbers doesn't really give one the best picture by itself, analyzing combatant to civilian death ratios is probably better than population death ratios as that gives you a better idea at how careful parties are at reducing civilian casualties. Unfortunately Hamas also uses tactics that are designed to increase civilian casualties as well which further complicates comparative analysis.
[0] https://en.wikipedia.org/wiki/ORB_survey_of_Iraq_War_casualt...