I'm interested in reading a good honest article about 64-bit and what this means for Apple vs Windows vs Android, unfortunately this DED guy is really crazy and I can't trust a single word he says. Actually I just couldn't read more than a few paragraphs. He makes me sick.
It's not easy to explain when and how 64-bit are good or bad.
Often 64-bit architectures are presented using concepts valid many years ago, when 16-bit was cutting edge. In those years 16-bit CPUs basically had a 16-bit memory bus, a 16-bit instruction set, 16-bit internal data paths, 16-bit internal registers, 16-bit arithmetic logic units, 16-bit address space.
Modern 32-bit CPUs are quite different. External memory bus could be 64-bit or more, instruction set is much more complex and has SIMD extensions capable of handling vectors of data (not a single 32-bit number), internal data paths are insanely large, internal registers are definitely bigger than 32-bit, there are multiple ALUs of different kinds with SIMD capabilities. And some 32-bit CPUs are capable of handling more than 4GB of RAM through PAE support (basically an artificial extension of the addressing bits).
So, what is a 64-bit CPU ? 64-bit is basically a reference to the addressing space, pointers to memory locations have that size.
Advantage) 64-bit CPUs allows to natively address more than 2^32 = 4GB of RAM. Note that some 32-bit architectures have physical address extensions (PAE) to partially address this 32-bit limitation.
Advantage) Even if only 4GB (or less) are present, the 64-bit CPU still has a 64-bit virtual address space, that allows much more flexibility in memory mapping of large datasets (numerical analysis, movie and image processing, ...)
Disadvantage) Extending internal registers and path to support 64-bit address space has a small cost in term of silicon area and power consumption.
Myth) 64-bit CPUs do not have double processing power with respect to 32-bit one with the very same Arythmetic Logic Unit. Remember that 64-bit are only for the address space, the internal number crunching units are not changed by 32-bit to 64-bit transition.
Myth) While 32-bit means 2^32 = 4 GB support, this is not true for 64-bit. Current 64-bit architectures do not support 2^64 = huge_amount of memory. For example AMD64 architecture supports only 2^48 = 256TB of physical RAM, reserving remaining bits for improvement in the future. I am not sure about ARMv8, but I think 2^39.
Sorry for the wall of text. I hope it can help to clarify some marketing techno-bubbles.