I also looked it up that HDMI 2.1 consistantly gives VRR or Variable Refresh Rate support
Cables don't affect feature support except where specified (i.e. an "HDMI with Ethernet" cable is required for the inline ethernet feature to work). There are no "HDMI with VRR cables" because VRR is not a feature affected by cables. It will work the same on any cable since it does not have any dependency on any physical property of the cable. The "version" of the specification a feature was introduced in is not relevant, which is why HDMI cables do not have version numbers, they have speed ratings. There are no "HDMI 2.0 cables" or "HDMI 2.1 cables". There are High Speed HDMI cables and Ultra High Speed HDMI cables.
Also, The RX 570 does not support the HDMI 2.1 VRR protocol, FreeSync is achieved using the AMD FreeSync Over HDMI protocol, which predates the HDMI 2.1 Specification by several years and has no dependency on it. But this is what most monitors use when implementing FreeSync over HDMI anyway, the HDMI VRR protocol is not widely used yet.