This really bothers me. I understand the point of the article is that they're charging a lot of money for an inexperienced consultant and no bias (discrimination) was meant, however, age is irrelevant. There are a lot of very "experienced" 23 year olds, as long as you're asking them about the work they've done. There are a lot of people in their 50s with very little experience (as their actual experience is irrelevant to the topic at hand or their actual experience has been very repetitive).
I think we need to be a bit more conscious of unconscious bias towards age (in either direction).