It depends. A lot of the group adventure travel companies, for example, will arrange private trips for which they can take advantage of the expertise, local knowledge, relationships, etc. that come from running standardized group trips. But those are often setup around having guides. (But not necessarily.)

The big challenge is sort of touched on in the article. At the end of the day, most of the agent's money needs to come from hotel etc. commissions. It's hard to charge people a lot for planning a trip--at least to the degree that it's exposed as a discrete line item.

I never use travel agents for standard things (hotels/flights/cars) and only hire them for long, complex itineraries (2 countries, 8 cities in Asia over 4 weeks, etc.).

Both Conde Nast Traveler and Travel+Leisure Magazine publish A-List or "Gold List" travel agents who specialize in a certain region... These are not the guys that work in your local shopping centre or mall.