>>33730
>BMP only carries one less person.

And it isn't much smaller. Dimensions from wiki:

Stryker: 6.95 x 2.72 x 2.64 m (length x width x height)
BMP-2: 6.735 x 3.15 x 2.45 m

So, it is 20cm less by height and 20cm less by length, but wider by 40cm. Comparable, especially considering that BMP-2 has no real armor (it side is penetrated by 7.62x51, so even in Afghan they quickly made more armored version). Stryker is slightly more armored (at least reports from Middle East say that).