Nowadays, the proportion of talented commoners to moneyed elite is considerably greater than it was even 100 years ago, but the basic principle remains: foster connections among the elites, and give them first crack at any emerging talent. This way anyone with a potentially destabilizing talent becomes attached to the existing power structure at an impressionable age. Better to invite them in and dilute the pool a bit than risk them draining it later.
Any commoners who don't work out, they will drop without hesitation.
I'm not saying this is evil. If you were among the elite, you'd probably do the same thing. And I also don't propose that this was all cooked in a room full of cackling conspirators rubbing their hands together. It's just the way a power structure works. From their point of view, I'm quite sure they see this as noblesse oblige: they're just reaching out, "giving back" and trying to help useful and interesting people succeed. But it nevertheless has embedded in it the idea that the most important part of success is meeting people who already have power.
And as the complainant in the letter writes, it sounds like all the hoi polloi ("Group B") at TED actually buy into this as well. Maybe he should be working on something amazing instead of hoping Bill or Steve or Sergey notices him.