Kray's fastest computer at the time was 0.6 G Flops. Boeing's B1B flight simulator came in at 1.2 G flops. Boeing went wide. Kray went fast.
Because the 64 bit address space exceeds what is now demanded of even the announced fastest of supercomputers, 16 exabytes, and is why, since 2008, AVX instructions came into existence. AVX is 128 bit, AVX2 is 256 bit, and AVX-512, currently an Intel exclusive feature, is 512 bit.
Only reason I like a wide data container is more for handling financial calculations. With inflation etc spreadsheets have long had to use multiprecision algebra to cope.
Early games often failed when an 8-bit register rolled over and there was no overflow handler in the CPU to notice