Yes and No
A good but free to play manager is gathering and using his sources mostly for attackers.
Wingers, AMC and ST are the players someone want to invest, not only to increase their quality and skills but to keep them for many seasons.
So it's logic to search for young fast trainers for those positions.
Those are the positions the game gives bonus at rates (as they score and giving assists) than MC, GK and defenders, so it looks like they perform better.