Not as bad as it sounds...
First of all, the article is talking about 65+ folks, the ones who are already on Medicare (FYI, Medicare part "A" is free, part "B" comes directly out of your SS check, so the folks are already paying for it on their own).
What we're talking about is the "medigap" (supplemental coverage) that is on top of the part A/B. My son (who is under 65, but is on Medicare due to his full disability) has supplemental coverage through Blue Shield, and pays $99/month. There was no "pre-existing certification" that needed to be considered to get the coverage.
This is not to say that this will lead down another "path" (don't know their pre-Medicare/65 cost and who pays for it), but that could get expensive. In reality, most companies don't cover any medical insurance (pre/post 65). I've been lucky. Being retired and having a good many years of service with the company I retired from, I pay the "company rate" on health insurance (group cost, which is slightly less), but again, that's probably the exception.
The article does not say that they are going to eliminate insurance completely. In fact, they are raising the pension (remember those?) by $300/mo to help pay for the medigap coverage. Also, this is for salried (non-union) folks, which is the smaller group of retirees (the retired union folks still are covered by the current contract, but that's always up for negoation next time around). For the UAW retirees, it's "business as usual".
Dosen't eliminate the discussion related to "national health", but that's really a "sticky wicket", politically speaking.