The push to get away from the short machined extractor was......*drum roll*......that it was too expensive to machine the slides for it, and too expensive to machine the extractor design. The classic Sig Sauer pistol is a machined part gun.....so keep your grubby MIM hands off it Sig!
MIM is fine if used for the right application and done right. Outsourcing small parts to Brazil was a huge mistake several years ago. When was the last time a quality product came out of Brazil? Sig had some made in India and Taiwan recently too......I've lost track of things now days as they change vendors so often.
At this point, Sig really should consider discontinuing the classic line instead of cheapening its quality so that it ends up dying a disgraceful death. Keep the LE and Mil contract guns going(with machined parts), but focus on the P320 series which is designed with newer generation technology and was designed to incorporate MIM parts from conception. Plus, with all the P320 adoptions they are going to have plenty of demand.