Saskatchewan and Manitoba are also over-represented.

BC, Alberta, and Ontario are under-represented. Ontario, for example, is about 39% of the population of the provinces, but only 36% or so of the seats.

The allocation is an imperfect formula, to be sure. I doubt it makes much of a difference in practice, except as propaganda fuel for foreign influence operations driving Alberta separatism. The degree to which most provinces are under- or over-represented is less than 1%.