True from one point of view. But DIY can't always apply for everyone and researching /googling on the web can only take you so far right. There will always be situational variables, follow-up questions, leveraging from one's experience, unlisted opportunites etc.
Technically, anything can be DIY. Taxes, Accounting, Selling/Buying a Home, Plumbing, Remodelling your Home, Investing etc.
Question is, can a person on their own deliver better then someone else whom provides the paid service?
I'd say in many cases no. People get stuck, too much time, don't want to make costly mistakes, or will have questions.