alt-F2 has been doing what you need for over a decade, before Plasma even existed. Otherwise, the bottom bar does the same thing the top bar does in GNOME and Mac OS X - well, a little better, as it always shows your apps running incl some text instead of having just an image of the minimized stuff (Apple) or a very useful empty space (GNOME).
So how exactly is the bottom bar useless while the top bar is apparently Jesus' next coming, despite the top bar simply doing less than the bottom bar?
Don't tell me it's the global menu - probably the most stupid thing apple ever invented (aside from putting a bar on top instead of the bottom of the screen, making the screen corners useless)...
I have the feeling you judge 'usefulness' by 'what I am used to'... That's great for you but useless for everybody else, so I suggest to keep such ideas to yourself - as it's only relevant for you.