> Highly contentious issues absolutely should be left to the states to decide
Alas, if/when the Republican party gathers enough power to finally pass a federal abortion ban (or an indirect Fugitive Pregnancy Act) that "principle" will vanish into the memory-hole with all the rest. The minority who sincerely held the belief will be sidelined, again.
Another manifestation would be if state personnel and courts get conscripted into enforcing federal immigration policies.