A kitchen sink software implies an image of a kitchen sink filled with dirty dishes. But the solution is not to throw them all away and leave a single dish, still dirty, but at least looking manageable. The solution is to wash all dishes and put them neatly on the rack.
The idiom "everything but the kitchen sink" (and variant "everything including the kitchen sink") doesn't refer to a sink filled with dirty dishes. Rather, the kitchen sink (originally the kitchen stove) is being used as an example of a particularly bulky item. "Everything but the kitchen sink" means, roughly, everything except for what would be too large and/or absurd to include.
https://english.stackexchange.com/questions/96582/what-is-th...
Really, because mozilla seamonkey tried that. How do you think that went for them?