Well then you would assume wrong, since x86 does not limit the modern CPU that much as they use micro-code to fit the instructions to the hardware, x86 ops are just translated to a way the CPU can process them best.
Implying that current desktop processors from AMD and Intel are "old tech" is ludicrous, the comment that "Cell is of a newer architecture with better optimisations and engineering effort" is even more ridiculous as the Phenom and Core2 are actually far and away more advanced than the cell is and are much more intelligent CPUs, compared to the cell which is a more like a VLIW processor being excessively compiler dependant and difficult to optimise and near impossible to keep fully utilised in something as complex as a game environment.
Cell was not built to be the most powerful processor, it was built to offer as much theoretical power per transistor, as a result it IS a compromised design since engineering trade-offs were made, it lacks in order processing, branch prediction, and its SPEs have limited functionality. Its main PPC based CPU is also stoneage compared to something like the Core 2.