They are not exactly hands-off, the admin has actually continued many of the policies they criticized Trump for.
But more generally Biden's problem is that immigration is to the Democratic party what Social Security is the GOP, a third rail topic. There are significant factions in the democratic party, factions that bring a lot of the necessary energy to the party, who believe in an open or nearly open border. It's concept where as a liberal i can applaud the sentiment intellectually but understand that it's insanity in practice. Somehow the sane part of the Democratic party has to *quietly* bring the uber-immigration-progressive part of the party into line with the public, whose position in big majorities across both parties is that immigration chaos in untenable. The other part of the dance is that Biden knows he needs to make a deal with the GOP on immigration and the GOP knows it as well and both sides are strategizing how to avoid the other side getting more credit with the voters.