Why no WebGL for 32 bit OS? (Technical reasons?)

I was trying to create a web game with a 32-bit os and got some nasty errors. After some research I found out that 64-bit OS is needed. Why can't Unity export web games (without the player) on 32-bit?

I played around with "Phaser" (allows the creation of HTML5 games (and also the uses WebGL)) and everything was fine.

Is there a technical reason for Unity's lack of support for 32-bit OS?

Will Unity allow to export web games on 32-bit machines in the future?

 

Suggest reading:

http://forum.unity3d.com/threads/webgl-32-bit-vs-64-bit-os.338307/

 

Thanks for the link, but as far as I can see, there are no technical reasons mentioned. After doing a bit more research though, I came across "Emscripten" which is only available in 64-bit. I guess this is the reason behind it.

Thanks again.

 

Jonas answers pretty well with the scope of the engine from his first response in his thread.
In this case Phaser is lighter weight with 2D only, so not a good comparison.

 

Oh, so it's about memory. This explains why content can't be run on 32-bit operating systems (although I believe that firefox and chrome are working on it?), but it doesn't say why it can't be compiled with one.

However, from my research I found out it's Emscripten's fault (...i think).