Not everyone is internet savvy. Not everyone knows what they want. Not everyone knows what they can afford. Not everyone comes from a history of property ownership. Some people need assistance on things that others can self-serve.
Real estate agents, even the so-called "buyer's agent," are the house equivalent of "used car salesman."
Just like you shouldn't trust a used car salesman to tell you what car would fit your needs and you can afford, you shouldn't trust a real estate agent to tell you what house would fit your needs and you can afford.