Are the barriers faced by African American athletes today the same as those faced by African American athletes in the 20th century?
To some extent, they are still the same and in other ways they are not.
Black athletes no longer have to deal with overt racism and exclusion. There are no Negro Leagues in baseball anymore. There is nothing like Adolph Rupp refusing to recruit blacks to play basketball for the U. of Kentucky. Those are completely a thing of the past.
However, black athletes still have to overcome stereotyping that limits the roles they can play and the ways in which they are perceived. There are, for example, still very few black quarterbacks in the NFL. It is not as bad as the old days, but I can not think of more than 5 blacks starting at quarterback in the NFL.
As another example, look at the way the NBA has been treating its players lately. One can certainly argue that the league is trying to make them seem "less black" and less threatening to a white audience. Many people think that the dress code imposed on players a couple years ago was meant to prevent players from showing up at games looking too much like gangsters. The new rules about not reacting to refs' calls and about getting suspended for too many technical fouls are also seen by some as attempts to make the players seem less threatening.
So, while blacks are no longer excluded from playing sports, one can argue that they still face stereotyping from white executives and white audiences for whom they perform.
Some of the problems that have occurred in the NBA are due to the caliber of players who are now recruited. Since younger players (18, 19) are being allowed into the sport, they are sometimes rather immature and cause behavioral problems. The problem is not bias on the part of the owners or anyone else; the problem is the actions of the players who are not mature, who have never been out of their old neighborhoods before and are overwhelmed by their own success. Now, the NBA has to be a nanny to these players so that they will remain eligible.
Also, in college sports, there are some rather unconscionable head coaches such as the recently retired coach of the Florida Seminoles who, records show, recruited convicted felons. Consequently, these felon/ball players did not conduct themselves too well. Their actions have nothing to do with racism; they simply were not exactly upright citizens.
The only barriers that African Americans face in sports are the same as those other athletes face: They must conduct themselves appropriately.
I think there are still many barriers obstructing sporting success for black African American sportmen and women today as poverty remains an enduring one, particulary in today's recession-hit times. It is sad that so many young black males are still so hard to reach and are underachieving in lots of areas. In sport, rich people will always have the advantage in activities such as tennis, horse-riding and skiing as these activities are expensive. It would be good to see some positive discrimination in some of the more elite sports.
I think it is important to note the changes in sporting that has removed a number of barriers that formerly prevented black players achieving sporting success. Certainly, if you will pardon the sporting metaphor, there is more of a level playing field in today's sporting world, but at the same time I agree with the remarks made in #2 about the dangers of stereotyping. Perhaps there are still barriers, but they are more hidden in today's world of Political Correctness.
I believe that there is little to no discrimination in professional sports nowadays. I think that coaches, owners, fans, and even other players have the mentality of "if you are good enough to be able to play at this level, who cares what color your skin is". Many people, including myself, are so fascinated by players and what they can do that they cheer for whoever plays the best, not whoever has the "best skin color". African American athletes, and all athletes that are minorities, are treated the same (as far as I can tell) as everyone else. They must follow the rules of the games, play their best, try their hardest, and be a good sport, on and off the field, court, etc.
Hope this helps!