In a frictionless market it would make sense to do that. But as Coase pointed out nearly a century ago[1] forming and monitoring the relationships that allow specialization involves a certain amount of overhead. At a certain point going through the hiring or vetting process to utilize another person's skills makes sense, but it looks like the author is very far from that point.

[1]https://en.wikipedia.org/wiki/The_Nature_of_the_Firm