That's an... odd perspective. AMD64 was a huge threat to Intel. It dominated the then flagship P4 and completely destroyed Intel's attempt to force us into an "Itanium everywhere" future.

The fact it didn't leave AMD in charge of the x86-compatible market owes more to their superb Israeli chip design team being able to pull them out of the frying pan.

In order to take significant market share, AMD will either need to offer superior price/performance and/or superior performance/watt. Both are unlikely because at 28nm, by the time the A1100 hits the market it will effectively be two manufacturing processes behind Intel's 14nm. Manufacturing process size makes a big difference in production costs, as well as in power efficiency. The microarchitecture won't even be a factor with that great a disparity.

ISAs eat the market from the bottom-up.

x86 is at risk here.

Especially with AMDs ability to throw GPU hardware on the CPU. ARM eats the bottom end on a $/Watt model, and the GPU eats the top end on a raw performance model.

Considering AMD64 took down the Itanium and basically defined the industry, it has a ways to go and Intel's response to AMD64 might be instructive.