You're right about my error with the definition and I'm no physician so I'll defer. But it was certainly a death sentence in my family. Still, if survival is possible I wouldn't wish death on anyone who suffers from it to prove my point.
It was bad. He became dependent on prednisone and inhalers to breath. And, well, if you've ever seen bloating and weight gain from prednisone you'd know what he went through. And the prednisone caused secondary infections from impaired immune function. He was dependent on an oxygen concentrator, which required bottled oxygen to be available in the event of a power failure. And a trip to the ER if the bottle emptied.
He described COPD as like downing in slow motion.
Any doc whose seen this before would know the story.
Anyway, of course, none of this I'd wish on Nimoy or anyone else.