Is an android supercomputer possible?

I never understood why devices don't get over 1GB of RAM. My ancient N1 has 512MB RAM, while my brand spanking new TF Prime only has 1GB RAM... The CPU has increased 5-fold (aggregated clockspeed alone) while RAM couldn't more than double in size?

That got me thinking, suppose I'm looking for an android supercomputer - something with specs that are way far ahead of anything out there today - think high-end gaming PC specs running android. What's stopping manufacturers from making them?

I undrestand CPU is basically just ARM, and that's a few years behind x86, though android can run on x86. But what about the technical efficacy of everything else?