Engine wear and emissions systems

This highly polished cyl. is from a customers ISC 8.3L with 2007 emissions. Engine was in constant derate due to blow-by. Cummins has a sensor to measure blow by and reduces HP to force the repair and comply with 2007 emissions standards. What I find interesting is that if this was a pre 2007 engine, even with the engine wear (Dusted @ 20,000miles) this bus would have continued to run. Due to the emissions standards, we are looking at a $15,000 repair