Not quite sure what people think premium travelers will do... thanks to rollover I'm swimming in MQMs and don't care about earning those anymore. Yes they've cut off elite bonus miles for KE tickets, but that's not enough to force me onto an inconvenient DL metal route or more expensive DL ticket. I'm sure this change sucks for a lot of people, and DL are cheeseballs for the way they're implementing the cuts, but it's not going to change my behavior - I'll keep flying KE.
Doesn't matter how much rollover you have, you need to meet the spend requirement or Amex waiver amount to keep status starting next year.