Right. It's like saying that the PCs in a regular D&D game are the first ones to rediscover magic in 1000 years. It adds texture to how they play their characters but isn't intended to actually limit their character choices.I believe the point is that the arcanosphere is a narrative conceit that restricts the dissemination of magic across Earth. It’s not meant to overly impact PC mechanics outside of the need to find more potent magic items to be a source.