At first glance, I love the idea of the prompt being in a static position, separated from the output. Surprised that this is the first time I've seen something like that.
I effectively have that by sticking newlines into my PS1 variable.
And, yes, it's because its easier to track when the prompt is always in the same place after every command.
The standard prompt is PS1, which after every command, places the cursor at some point in the line that depends on the width of $PS1 contents.
By appending a newline to the existing PS1 variable, the cursor is always at the same point after every command - far left on the last line.
I did play with embedding the last command into the PS1 variable too, so that not only is the cursor at a constant position, but the line above it prints the last command too (!! or something like that)