Hm, intriquing question. Like you I've mostly made utp cables (and coax before that) myself. I'd declare it nearly impossible for the pinout to change from cat5 to cat6 to cat7, as the cables are backward compatible. And I've not found any evidence for changes in pinout, so far.
Having said that, I have a few possible causes for your 'color confusion':
- The cables are possibly made by unexperienced/uninterested people, and they just 'made it work' by creating a 1:1 connection, regardless of wire pairs (simple wiretest equipment can't detect pairing, only correct connections)
- The wires have a non-color-related pairing (highly unlikely though), you'd have to cut open a cable to verify
When aiming for cat6/cat7 speeds, I'd verify that the cables are pair-connected as required (and ideally shielded as well) to avoid hard to debug networking issues. The shielding requirements for cat6/cat7 make it quite hard to make these yourself, unless you have access to the professional tools for crimping that type of cable.