Traditionally (with ICC) the criticism has been that it just checks the vendor string for "GenuineIntel" instead of actually checking for feature support with CPUID. People just want the option to be able to just check just for feature support.
A given "feature" does not behave identically on different CPUs. To generate optimal code, you need to know which model is being targeted to make codegen decisions. It is simply not reasonable to expect Intel to do the work on their compiler to figure that all out and test it for competing vendor chips.
If you want more, use a different compiler, period. $VENDOR spends money on their compiler to support their chips, not to appease every whining, butt-hurt user on the Interwebz that thinks $BIGCO owes them something on a competing chip.
