Why not deism?

[Inqwizitor]

Atheism is an amorphous description of a lack of belief in a god or gods. It could mean that someone has no faith in a religious idea about what a god or gods means, or it could be a philosophical conviction of some kind. 

Something I'm curious about is why deism is virtually non-existent nowadays. There are arguments for the existence of "God", that actually, in the end, don't amount to much more than a hypothetical Prime Mover, or "something" — we don't know what — that is the source of reason, volition and material phenomena. 

Is deism pointless or even dishonest, because it's asserting something as knowledge that we cannot know? Did you ever seriously consider it instead of atheism? Or is there any practical difference?

Deism only avoids some of theism's intellectual problems.   It does not avoid others.   In the end it fails to address the question of why one should put up with it.

I guess it depends on your perspective. While atheism doesn't put up any intellectual problems (because it doesn't really put up anything at all), naturalism does, and reductive or eliminative materialism do.