Here is my try at explaining it in layman terms, but I'm not 100% sure I got the meme completely right. I didn't do protein crystallography, only organometallics.

Crystallography is the dark magic art of turning nice really small crystals into pictures of molecules (or more precisely: 3D maps of electron density) The scientist in the meme wanted to measure the same protein, but under different pH conditions, so either adding some acid or some base while the crystals form. Then they hopefully get different structures at different pH values and can make a nice video animation like a flipbook to show the change in structure.

And I think the meme makes fun of the fact that the scientist did this experiment with a certain expectation and then that expectation happens but the scientist is surprised by it happening.

They chose a protein which is a reductase, meaning it can reduce the oxidation state of certain molecules. Such a reduction reaction is often dependant on pH value in organism (I think), therefore changing the pH value changes what the protein will do in the crystallization solution.