These northerly routing have been pretty common in years past. We call them "CAN Routes" and there are multiple different tracks that the command center can assign to aircraft both east bound and west bound.
Last year they were exceedingly rare as NAV-Canada did not have the staffing to allow this kind of traffic (thank you COVID-era firing of all ATC trainees). This lead to some pretty circuitous routes last year when storms came around. Aircraft from the west coast to east coast being routed up over Michigan in ZMP and then a hard turn south into ZOB's airspace before proceeding eastbound were pretty common. ZYZ wasn't even accepting point-outs. Canada stay in Canada and USA stay in USA was the standard.
Methinks this year the return of Can-routes will be a thing. Potentially even more northernly routings, i.e. up and over to ZWG before turning south, are possible this summer. Staffing levels at the US ARTCCs this summer are going to have an effect on traffic at some point.
Peace