This is a clean example of an ignoratio elenchi fallacy.
Statement B attempts to use Statement A to make an unrelated point that isn't necessarily untrue, but it is still unrelated.
This could be done with any combination of...
"Under capitalism, is..."
"Under , science is..."
They would all result in a statement that supports Speaker B, but is no longer relevant to what Speaker A stated, as the topic has changed. In this case, from science to capitalism.
I.e. It's an anti-capitalism meme attempting to use science to appeal to a broader audience through relevance fallacy. Both statements may be true, but do not belong in the same picture.
Unless, of course, "that's the joke" and I'm just that dumb.
Edit: I'm not a supporter of capitalism. But I am a supporter of science—haha, like it needs me to exist—and this is an interesting example of social science. It seems personal opinion is paramount to some individuals rather than unbiased assessment of the statement as a whole. Call me boring and autistic, but that's what science be and anything else isn't science, it's just personal opinion, belief, theory, etc.