I thought it was pretty well understood, to anybody paying attention at least, that there have been no official 6, 7, 8, or even 9G mobile networks yet, so of course 10G was a slightly quicker name for 10Gbps networking. It's maybe not an industry standard, but colloquially many datacenters will call a 10Gbps-capable network switch a "10G switch." This seems like an extension of that colloquialism to general consumer…
Maybe they don't think you should have to follow the industry to know what a company's advertising means?
It pissed me off to no end to hear the monopolist advertise their "10G network" ("with speeds starting at 200Mbps")
It was CLEARLY meant to mislead.