I think that the morphing of the Trumpers--who were often not Republicans in the first place--into anti-vaxxers is a whipsaw within the Republican party. Almost all Republican leaders who have been vaccinated--and would prefer that everyone would get vaccinated--are forced to defend the antivaxxers to save their voti9ng base. It's a dubious undertaking.
As that strategy fails, the whole party falls apart.
Not only is that dynamic hard for Canadians to understand, we're not so hot at understanding it either.