I totally agree. It kind of depends on your setup. The big difference is the amount of space that you must use. In soil plants can become rootbound. That doesn't truly exist in hydro. The thing in hydro is that there is no such thing as overwatering, but under oxygenating. If the roots have enough air, then you can let them rest in water. You can cram more plants into an area because of this. Yet, the problem is that you can't go too crazy because plants compete and force each other out.