There were rumors early in the downtime that it was the responsibility of various outside groups. Saying, "no, your data was not impacted" is pretty standard in light of those rumors, even if they weren't the main ones spreading around after the initial reports.

It doesn't make it sound like an attack, it's standard boilerplate to dispel any worries. It's natural for anyone to wonder downtime -> data loss? , so it's natural to reassure people that it wasn't the case.