Of course its the white Dwarf I can't seem to lay my hands on for some reason, i know I bought it...
So its a WD 'writter' not doing his research.
Squats are not extinct, they were retconed out of existence for 3 editions and then reappeared in 6th rewound to their early RT fluff.
- - - Updated - - -
It was also in 6th ed. Which I was stoked about as I had started a Squat IG army after acquiring a bunch of them.