These articles would be much more interesting to me if they all didn't end with and then they wrote a blog or partner still works. So both situations have them continuing to make income the old fashion way (ie. working). So they actually switched careers, they didn't retire. For them, they found a better way to make money because a decent blog will generate $3K/month which if they are looking at a $40K/yr income covers almost everything so they can let their wealth ride.
I could do the same by joining a multi-level marketing gimmick. I could easily pull $2-3K/month just hanging around at meetups/gym and selling the lastest weight loss plan. To me its the same thing, your selling something.
I would honestly like to see how people in their 30s handle not having the extra income, dealing with ups/downs in the markets. How they have to deal with withdrawing income, taxes, buying large ticket items like a new roof/vehicle, etc. That I would read, but I'm not going to read how to make a living by working.