It takes a variety of skills. Depending upon the endeavor - sometimes it takes technical skills, sometimes it takes sales skills, sometimes it takes marketing skills, sometimes it just takes the people skills to get to know the right people.
What it takes more than anything is drive. The most successful people out there typically have a tremendous amount of drive to pursue success.
I find that people who disregard skill do so because they have no clue as to why they're unsuccessful. The thing that would hurt their egos worst would be to admit to others and to themselves that they have no skill. The best thing that they could do is to look in the mirror, admit that they're lacking something, and work harder to find it.
Or how about you do a good job providing something people will pay money for. Unfortunately for tech people, what the market will pay money for isn't always what tech people want to build.
Funnily, I believe you're both right, that there are several paths to success.
One is the "knowing the right people, buddies/PR" route. I've known several sociopaths and unethical people that do well along that route. Many have the "skill" of making you believe they're your best buddy (and then backstab you), or to sell you a bridge (or sell you a shitty job with unpaid extra hours).
The other is to provide something people will pay for, excel, and get known - which also involves some sales and PR, or marketing, but depending on your profession can be going through the speaker circuits at conferences, writing a blog or some other way to convey expertise, or getting writeups for your product somehow, if it's B2C - see Paul Graham on why he hired a PR:
Knowing the right people, flirting with tech reporters, being good at PR etc
That is what gets you ahead.