The removal of the excluded/restricted abilities was a difficult choice. The reason they were initially included was for balance purposes. Non-humans gained racial bonuses and humans did not. So, you need to place some type of hindrance on non-humans.
The problem for me is that I do not like artificial mechanics. Why couldn't race X have ability Y? The only reason that makes sense would somehow be because of the setting. But those restrictions are also difficult to justify. Are we to believe that elves never engage in commerce or that dwarves never try to cast spells? And then with restricted abilities, the idea is that a PC cannot begin with them, but can learn them later. Well, why? How is it that NPC in their communities could have them, but a PC couldn't?
I do not like justifying things by saying it has to be that way to balance out the rules. Think of AD&D. Elves live thousands of years, and yet have a level cap. Why is a creature that can live 10 times as long as a human restricted to a lower level? Is there some type of mental defect on elves? It was bizarre and many people ignored the level limits or modified them in some way.
Then, there is another reason - simplicity. If you are making a non-human you would have to constantly check to make sure the ability you wanted was one you could take a character creation. That seemed an unnecessary complication.