The HDMI with ethernet cable lets you connect all your gear to a network without using a separate ethernet cable for each device. Of course, the equipment the cable is attached to has to support this feature. So far, few if any devices, do. So essentially, HDMI with ethernet cables aren't required for anything.
There is an advantage to using a HDMI with ethernet cable if you are using audio return channel (ARC) with a long cable. The changes made to support ethernet also make for a better environment for ARC. IOW you might be able to get ARC to work at a longer distance than it would otherwise.
If you aren't getting sparkles or worse with your current cable, changing the cable won't make any difference.