Then it would seem sanctuary city and state practices should become a thing of the past, because they don't comport with Federal law.
Absolutely.
And I believe that SCOTUS, if they ever hear a case regarding sanctuary cities, would vote to strike down those sanctuary laws as unconstitutional.
Can’t, at the moment, think of a situation where a SCOTUS case would arise, but it could happen.
Who said: “ A country without borders is no country at all”.