With current system, I can maintain Emerald (in two years) by flying four round-trips JFK-TPE in D Class (Business Basic Fare) plus a round-trip TPE-NRT in Y/B/M (Economy Flex). With the new system, I would still be 50 status points short to maintain Emerald if I took five round-trip JFK-TPE in D class.
Another significant downgrade is the status points for taking flights from Skyteam carriers. The highest status points a member can get by flying any skyteam members is 30 only.