Good question! I read two different Amazon press releases on this but still had to come here for the answer. It seems strange they don't want to advertise the ISA of a compute product - does marketing think it might scare people away?
It seems they don't document the ISA for any instance types. This could be deliberate (and unrelated to marketing) in case they decide to pull features from the instance types in a microcode update. Without any ISA specifics, previous customer commitments towards instance types would still apply.
The part under “Performance specifications“? That's not really a commitment to functionality, especially since there is no vendor specification (ISA reference manual) for many of those model names given. Intel even published a FAQ about missing specifications: https://www.intel.com/content/www/us/en/support/articles/000...
