True but actually unimportant, they didn't observe any background neutrinos but the effect of them on the structure of the cosmic microwave background. Besides

True but actually unimportant, they didn't observe any background neutrinos but the effect of them on the structure of the cosmic microwave background. Besides that neutrinos have a mass and are therefore expected to travel at subluminal speed and should arrive after photons from the same event however a deviation from the speed of light has not yet been measured (except in Italy but there in the wrong direction).