The answer to the first question is easy . . . they're politicians and they're attempting to seek the favor of minority voters by words. Words are easy and liberals hope that enough words will keep them in power. And words are necessary since liberal policies are largely responsible for devastating the inner cities of America and destroying so many black families.
The answer to the second question is just as easy . . . money. The Congressional Black Caucus is clearly hoping to, sooner or later, get another government handout for their constituents. This time in the guise of reparations to the descendants of slaves.
Apologies for slavery are owed and reparations should be paid if any slave owners are still around and any former slaves can be found to pay. But, unless someone from one group or the other has found the Fountain of Youth, I doubt that anyone who had any personal involvement with the evil of slavery is still alive.