The blue post explainers are always pretty vague. The CAD one says “From time to time, it’s necessary to make changes to certain pricing based on a variety of factors, including global and regional market conditions.”
It would be crystal clear if they had said something like “Canada is implementing a new digital goods service tax, in addition to existing GST, which is effective 1-Jun-2021 and will be included in your base game-time price, effective 16-Dec-2020, since it is to be collected by Blizzard Entertainment, which is a foreign business for Canadians, and thus does not appear as an itemized tax at checkout.”
That explanation is speculation, but a crystal clear statement like that would explain to a lot of unhappy Canadians their government is to blame (if that were the case) or if it’s just Blizzard being greedy because they now pay more after exchange unless they buy subs–nobody else is in that boat except NZ, so why CA and why now when the tax doesn’t hit 'til summer?
P.S. …and how is it game-time is affected by “regional market conditions,” but subs are not? WoW pricing is the same for subs/game-time in every other region, so why the sudden different for CA?