Like any other theory it would require some proof of some kind to move the present 'soup' theory off of the blocks & into the dumpster.
Though I prefer this one over the soup! It makes much more sense, given the write-up you presented, than the "lying around for a few million years" ooze that suddenly combines, Frankenstein-like, to form the simple start of life.
We'll probably never know, like many other things out of the grasp of present day human knowledge.
Life on other worlds? Perhaps. It would certainly seem likely given that there are billions of galaxies each with trillions of stars. The odds would seem to be that favor. Unfortunately, we'd probably never meet any other life form since we're bound to our own solar system. Unless we somehow manage to get past the light speed limitation, which is HIGHLY unlikely & impossible with what we know today. With all of our past decades of searching for radio signals of some sort we still haven't found anything artificial beaming around. Then again, we've only been looking for the past what, 30 years? 30 light years is still awfully close to home, radio-wise.
Close encounters is still in the world of sci-fi & is likely to forever remain that way.
But can we, someday soon, get off of our collective keister's & get something started on Mars? Please! All it would take is one small comet or asteroid & all that we've accomplshed, all that we've done, Michelangelo, the Taj Mahal, Einstein, Plato, etc. is lost.

Enough of this philosophical banter............