The minute you save a little money and have a few investments it can start to become complicated quickly. Yet you don't have/make enough money to justify the expense of hiring a professional to properly sort it out. This actually can become a giant headache because it is difficult to be certain that you've done it correctly and not overpaid.

Sure, if you only have a W-2 then it is pretty simple. The issue is that over time people have a tendency to accrue other tax reportable activities as a function of age. It actively discourages people from making some types of potentially productive investments because of the additional tax complexity.