DisplayPort is widely available on business-class laptops, gaming laptops, all modern discrete graphics cards, all modern integrated video chipsets (although not all motherboards/devices will actually provide a port), etc.

You're actually diametrically opposite of reality here: the only devices which do not widely support DisplayPort are cheap crap intended for the low-end consumer market, and stuff exclusively targeted at the living room market like consoles and media-stick PCs.

Even something as pedestrian as my old Thinkpad from 2010 supports it.