All HDMI cables are capable of HDCP2.2. Not ALL cables can handle 18Gb/s speed. The only time you need a cable with 18Gb/s speed is when you have 4K content that is actually pushing that much speed. Otherwise, you are typically fine with standard HDMI cables.
Didn't we talk about this already?
If not, the real goal of any mention of HDCP2.2 or HDMI 2.0 is to ensure that every piece of the chain supports HDMI2.0 and HDCP2.2. The projector does, and that's the last piece. While HDMI is backwards compatible, there are certain devices that are newer which may require HDCP2.2 compliance, but the cable isn't one of those things. It just needs the capacity to support 18Gb/s for 4K. The rest will be handled automatically.
Monoprice has some very good 18Gb/s rated HDMI cables for not a lot of cash if you want to try them out. Go skinny or go home.