A 'perfect angle' from a guided setup absolutely CAN, and usually will, make an edge much sharper for most people. If it doesn't, it's usually because the job didn't get finished i.e., the edge was not fully apexed. I had to butt heads with my guided setups a while, before realizing the lack of a truly sharp edge was due to the fact that the very edge hadn't been thinned quite completely, in spite of the 'pretty' shiny bevels left above the edge. That imperfection wasn't the guided sharpener's limitation; it was mine. I didn't take it far enough. If the edge is 1.) taken to a complete apex, and 2.) refined, all at the same perfectly controlled angle, the result will always be better than the same effort made at a less than perfectly-controlled angle. A steadily-controlled angle is all-the-more important as the edge gets closer to apex. Any variation in angle, when it's real close, can immediately degrade any previous good work done.
Most of us at least want to freehand perfectly, in spite of our own limitations. In doing so, we realize the primary goal, and the biggest challenge, is maintaining a steady angle. That's what the guides are designed for. Beyond that, it's still critical to take the very edge itself to it's full completion.
As to the original question, some people will do their best work with 'traditional' means, because that's what they've focused on learning to use. Others will find enough inspiration in more 'modern' tools to further motivate themselves to use them to excellent ends. It comes down to picking at least one method or system, and staying with it long enough to learn how to use it to it's fullest. Most people won't be patient enough to take it that far, but they might still get 'enough' out of their chosen method to keep them satisfied.
All over the forum here, you'll find 'experts' on stones, 'experts' on the EP or WEPS, and 'experts' on grinders or wheels. As demonstrated in their posts, these experts have done verifiably excellent work. So, is it really possible to say that one method or tool is any 'better' than any other? Any one tool can either be the 'best tool' or the 'worst tool', depending upon the experience, skill and patience of the individual using it.