It sounds to me like it is either a knowledge gap of which they may be unaware, or a personality issue. When hiring in the past, I looked for thoughtful, but honest answers-- even if the answer was "I don't know." Someone talking around the question or bullshitting me resulted in a no. Also, interviewers may be sensing some quality which hint that the interviewee would make existing employees' jobs harder. Dunno if this is happening, but things like talking bad about previous jobs, management, etc can turn folks off. Also, if one implies many previous jobs were problems the interviewer may assume that the employee was the issue instead.

I think personality issues are kind of overstated for interviews. Just about every industry has its fair share of jerks and sociopaths that throw people under the bus. Regardless, they have jobs, and almost all of them had to pass interviews to get into their respective companies. These are the workers that set the lower bar for entry into a job, and in the "right" companies, your personality would be passable by those standards to get hired.

But what did he interview for? There's a big difference between getting a customer support interview at Google and getting an engineering interview. He doesn't really say what he interviewed for.

Or for that matter, what kind of job he's looking for and what his skills are other than QA @ EA (was he writing automation, or doing gameplay testing?), an 18 year old developer (intern?) at IBM, and customer service at Amazon. And maybe that's part of the problem -- hiring managers don't know what he wants to do. (which is easier to get away with at a small company since you'll do a bit of everything, but larger companies are generally looking for someone to fill a specific role)

If he's consistently getting first interviews but not getting past that, then maybe his resume sounds better than his actual skill level.

To make this even more explicit: if OP can get interviews, then the resume (and the "on paper" job record) is clearly not an issue. The issue is interview technique, possibly the verbal description of the job history, but possibly something else (technical or social).

I second other comments elsewhere in the threads here to get a candid friend to help with interview practice.

There's the caveat on education.

From the other side of the fence, if a candidate has an atypical resume, the best course of action will be to interview to check their level.

You can't ignore the possibility of them being good autodidacts, but it will also lead to a very quick rejection if they're below those high expectations. It creates a cycle of quick interviews at prestigious places and quick rejections.