Downloadable 2005 beta of Spore?

There's no such thing. The 2005 video was mostly a mockup (created by a visual effect system called Swarm), not a real game.

Taken from the personal website of a Spore dev who worked on it:

Swarm, the swiss-army-knife visual effects system I wrote that has featured in all the games I've worked on. In addition to general visual effect usage, it's proven a very useful prototyping tool, which has led to it being abused in various interesting ways well beyond its original design remit.

In particular it was responsible for 70% of the original GDC 2005 Spore demo. (Thereby unfortunately fooling a lot of people into thinking the game had already been developed.)

http://www.andrewwillmott.com/talks/swarm-procedural-content

While i do agree that the early builds look fun and some do have much more content, to my knowledge its impossible to get early builds unless EA somehow manages to let people download those early builds.

https://www.youtube.com/watch?v=tpK1rZ3tkU4

This obviously is an early build of Spore in a genuinely playable state, at least to the extend at which it can be called a 'game' and be played and enjoyed.

Is there a way to play THIS?