How did they encourage it?
If I recall correctly Barrack Obama made public exhortations to Central, and South America to "Send all of your unaccompanied minors, then fuck and make more to send"
Then they concocted some 'Dreamer' bill which he ended up having to enact by E.O., because it was such an obvious two part scam.
Joe Biden reassigned border patrol to essentially glad hand incoming migrants, but somehow you have a problem with the Trump administration cutting the dead wood off federal bureaucracy.
Those camps you saw with the people behind chain fences? Those existed under Biden and Obama. The treatment was just as inhumane.
And those Illegal Aliens were admitted into the country under Deferred Enforced Departure, of both Obama and Biden.
It's just the news media is mostly liberal owned and there's no incentive for right-wing media to focus on deportation when the Democrats are doing it because right wing audiences perceive it as a good thing.
Nobody is denying that's how deportations were counted under Obama and Biden, those are undeniable facts.