It is a common joke construct in english to use the one is a X, the other is Y to confound user expectation. (although X and Y can be reversed for purposes of making the joke more funny)
The Joke starts with a question in the format what is the difference between A & B where one of these A is to be the Butt of the joke. The answer then says one is X where X is a number of qualities, probably laudable, obviously describing A, then the punchline is the description the other is Y with all negative qualities in such a way that you realize that the previous description of X which you thought was referring to A was actually referring to B and the negative Y is a particularly mean spirited description of A. One common variant if you have the negative Y values described first you will just say
'Well one is Y (all negative values) and the other one is A (just repeating the name)'
The comment was written in such a way that it functioned like one of those jokes. I unfortunately cannot think of one of these jokes right now, but for an example of how the reversed version works you might have something like this:
What is the difference between X and Ted Bundy?
Well one is an insane Republican murdering abuser of women, and the other is Ted Bundy.
No particular person was thought of as being represented by X when this example joke was formulated.
The grandparent's joke misses the mark, though. It should have been "singularity is now used for science too!" to make it work. As it stands, he just piled on to the expected list of benefits of singularity without the necessary subversion of expectation.