The Google Maps change does only seems to be visible for people with US IPs. But I assume that Apple Maps, Mapquest, Mapbox, Bing (TIL Bing has a map feature), etc all use GNIS to label features too, right? None of them have changed the name yet. Seems unlikely that all of them would still be out-of-sync with upstream, and let Google drink their milkshake like this.

According to this Wired article:

In fact, the map for the federal government’s Geographic Names Information System database, which informs these changes, still showed Lake Ontario as of Sunday morning, with a note that the maps are “in the process of being updated to reflect this name change.”

Sure looks to me like Google made the change before the basemaps were updated. It’s now 23:40 EDT Sunday, and GNIS still says Lake Ontario…so yeah, I think this is on them. Dear Leader told them to jump, and they rushed to show him how high they could get.