Bi direction means it can send info both ways, it doesn't mean that's it an input port. Example, ARC, which is audio return channel. It sends audio back through an output port. Doesn't make it an input port.
In 30 years of PC, I'm not sure I've ever seen a laptop with a native HDMI input port. Can you add one with USB/Mini PCI'express/expressport/thunderbolt/whatever connectors, sure, but built in, no. And IF, and a BIG IF, that a laptop did have an HDMI input, you would see 2 ports on the PC because one would certainly be an output port as well.