The SM, by definition, doesn't include gravity. And just because both photons and hypothetical gravitons are massless doesn't mean the phenomena would be similar in any way. We know they are not, otherwise we would have a consistent theory of quantum gravity by now. @ohwilleke: You underestimate the number of events we will get. Let's say conservatively 1 NS event in 1 year of running, ignoring that the sensitivity improved over time. In a year, with twice the sensitivity, we would expect 8 events per year. In ~3 years, with the full sensitivity, we might get something like 20-30 per year. Add KAGRA and the number will get even larger. Add INDIGO and we might get more than 100 events per year. And then we can build the Einstein telescope which will see these events routinely. Of course we might have been extremely lucky with this NS event, but that is unlikely. For binary black hole mergers the situation is even better, with 4 events observed already we can be quite sure they are not extremely uncommon. That was said by the scientists during the press conference.