For a while, as new systems were coming online, GPS was being used as a generic term, and the US system was being referred to by its original name, NAVSTAR.
But only purists would do that, and everyone else kept saying GPS to refer to the US system, so the new term GNSS was invented as the generic.
I try to say NAVSTAR and GNSS to avoid the ambiguous GPS, just like I say "gridiron" and "soccer" to avoid "football".
Unfortunately, anyone who knows what the acronym GNSS stands for probably also already knows Galileo is such a system. So changing the title to 'Galileo GNSS outage' probably wouldn't clarify matters :(
Indeed, the second paragraph spells out that this is a Global Navigation Satellite System (GNSS) and places it in context with GPS, GLONASS, and BeiDou
For a while, as new systems were coming online, GPS was being used as a generic term, and the US system was being referred to by its original name, NAVSTAR.
But only purists would do that, and everyone else kept saying GPS to refer to the US system, so the new term GNSS was invented as the generic.
I try to say NAVSTAR and GNSS to avoid the ambiguous GPS, just like I say "gridiron" and "soccer" to avoid "football".