The 15th Amendment gave all United States citizens a right to vote no matter what their race, color, or previous condition of servitude. During the Jim Crow era the southern states simply acted as if the 15th amendment didn't exist. They denied black citizens the right to vote on the flimiest of excuses. The federal government never really forced the issue in the Voter Rights Aoc became law.
The United States should have done a better job of enforcing the fifteenth amendment in the early part of the 20th Century. If the government had, the U.S. might have seen more rapid progress toward racial equality. As is, the U.S. still has major problems with voter disenfranchisement. it's hard to imagine the country wouldn't have benefited from stricter early enforcement.
I believe the fifteenth amendment should have been enforced better in the early 1900's. I believe the reason it was not was due to the Republican Party. The party wanted to remain viable but thought that the black population needed to be held back in order for them maintain a majority. Clearly this amendment was not followed in several instances and there was very little, if nothing, done to uphold it.
No, the 15th Amendment should not have been better enforced in the early 1900s, because for the most part it was soundly enforced. Enforcing the 15th Amendment cannot completely prevent racism from happening at some points. For the most part, people tried to follow the 15th Amendment and bring about equality.