What do you mean by "maybe"? Eastern Ontario contains the 4th largest metropolitan area in Canada (Ottawa) which is a very reasonable comparator, the density is 195/km.
IT's just there are large parts of what is classified as "eastern Ontario" that is kinda similar to the near-north ; not arable, shield & cottage country, and sparsely populated. So it doesn't feel fair. But yes, Ottawa clearly a major centre.
