Of course, quoting the abstract is a little unfair. The abstract needs to be short so there's no time to explain what the hell a Sato-Levine invariant is. Perhaps the actual paper is a lot clearer.
I think you are guessing wrong. A 4-manifold, that I can more or less understand (and that is about as far as one can get, as there are several slightly different definitions in common use), but immersed surfaces in manifolds? And I do not think that is because I haven't done abstract math since graduating. One can graduate in mathematics without encountering any manifold, for example by focussing more on applied fields such as discrete math, analysis, or statistics.
I do not think that that abstract is necessarily bad, though. It seems to mention sufficiently many terms to sell it to the target audience of, say, 100 people world-wide. If you do not know any of these, you should read something more basic.
Why on Earth would a common joe want to read that paper anyhow? What could it possibly do for them?