Is this true? I never read anything about it. I got the feeling that even in DA:O, the game had a more easy path to do it. And since you unlock missions on the war table, I doubt every companion could be available at the start. I can be wrong too of course.
Well, conpanions might be divided in two group:recruited in Orlais and recruited in Ferelden.
The First main quest, who will probably open The others, is likely The mage-templar one, and I don't think any Companion will be recruited here. After that I guess you Can do different main/recruitment quests in Ferelden, and you have The option to choose which one.
I didn't mean you can recruit all six from The starts, but that you'll still have freedom between a Group of them.