The motivations of AWT is easy to understand even for layman people - this is the main advantage of this rudimentary "theory of everything". The main point is, the light is spreading in waves through space-time and here's no principal difference between vacuum forming the space and the vacuum, forming the particles of matter. So we can say, the light is spreading through vacuum in waves, because the vacuum is behaving like common matter from this perspective.

But as we know, the light can transfer energy of virtually unlimited density, which effectively rules out all previous thin/sparse models of luminiferous aether. It means, all previous models of sparse Aether were based on very trivial misunderstanding of the concept of luminiferous Aether, which was common both for Aether proponents, both for Aether deniers. Only Sir Oliver J. Lodge has recognized the relevance of the dense Aether model explicitly, but his insight was ignored even by Aether proponents (T.J.J.See in particular) and as such it was completely forgotten.

Instead of this, the Aether must behave like very dense particle system and as we can demonstrate later, from this assumption the foamy structure of vacuum and transversal character of light wave spreading can be deduced - between many other things.