You aren't mentally overloaded by seeing a lot of buttons, many are. Consider the number of people who couldn't figure out how to stop the flashing of the clock on their VCR- that was very real.
Many people want one remote that handles all switching and it really is a good way to prevent confusion when handling remote controls- some look similar, but won't operate the piece that needs to be controlled at that time. One customer who had a Harmony which ALWAYS worked for me would frequently press the 'Device' button, then another botton for some function thta he never bother to remember. The color of the screen changes when this button is pressed and I would get messages stating that "It's not working, again", but his impatience was the cause. Some people press more buttons in quick succession, many press the buttons harder and neither works. Equipment won't do what's needed if they receive commands without enough time for them to process- AVRs often needed five seconds after the Power button had been pressed before the input commands would function.
Another reason for a universal remote, especially with RF communication- people don't always want to see ANY equipment and when the interior detonator gets their way, well, you know.....hiding the equipment makes proper operation almost impossble. without one remote that doesn't need line of sight.
Another problem- some remote controls were terribly designed. The one below has buttons on both faces and in order to operate some frequently used functions, slider switches need to be used. It's hard enough to read it in daylight and almost impossible in dim light.