I have a laptop that draws 240W over a square slim tip, and recently saw a 240W GaN power brick. Like the photo in the article, it's comparable to an iPhone in size, but what prevented me from buying it was the weight (400g) and the price ($155 IIRC).

I think the sweet spot of GaN is in wall adapters that deliver 18-45W over USB-A/C for mobile devices rather than PSUs where the size/weight doesn't matter as much.