Re: If Satoshi's paper was submitted in academia would it earn a Masters or PhD?
Nope. A Masters or PhD thesis with less than 50 pages is too little.
Sadly that is true. A Ph.D thesis should have a minimum of 200-300 pages. That said, I don't think that it will be that hard to add some of the finer details to the original BTC paper and "elongate" it a bit.
That would be an interesting piece of art if done correctly!