Boeing is well aware of the issue.
The slang term for it is "Beached Whale" coined after an occurrence several years ago in OAK involving the Southwest Shamu 737 on takeoff.
The official description is a "rate jam of the nose wheel steering metering valve".
In the 3 event I am aware of recently, two of which left the runway surface, the crews applied full opposite direction corrective measures with no effect. The key in all of these events is that the crew continued to employ stopping effort during the attempted directional corrections. So in the cases of the aircraft departing the runway surface they did so at slow speed.
The analysis of one of the aircraft found debris in the NLG steering filter but the findings were not conclusive. The other two teardowns resulted in no findings.
As the TSB report states the rate of occurrence is within Boeing Safety acceptable risk of less than 10 to -9. Until there is a hull loss they are simply going to accept this problem.