Varies by province. In Quebec, they have a similar absence rule to what you described (for being outside Quebec even if in another Canadian province), but they

Varies by province. In Quebec, they have a similar absence rule to what you described (for being outside Quebec even if in another Canadian province), but they entirely exclude absences of under 21 days from the calculation, and they have a bunch of exceptions, including a "once every 7 years" exception for miscellaneous personal reasons including leisure vacations that just requires you to notify them in order to qualify. And in theory they will reimburse expenses outside of Quebec, even outside of Canada, but only at Quebec's very low rates. Still, yeah, very different than how US health insurance works, agreed.