Why did we stopped using a term programmer, which is exclusive to our position and opted for developer instead?

as far as I understand it...

it's like the difference between the graphic designer and the prepress operator.

they both do graphics... but the designer invents and evolve the graphics where as the prepress operator just executes what was designed.

So.. the developer designs... and a programmer executes.

Programmer can be used for person who specialize on specific language and use that lang. mostly. Like java programmer etc. but developer develops an app or tool with the lang. that does the job and may use multiple or may develop/design other parts of the app/tool which do not require coding/programming.
Ps. Thats my way of thinking.