Classism in Elderling society? (spoilers RotE books incl Blood of Dragons)

[Valarya]

I've always been interested in how the dragons completely died out. While your post points to some reasons why many of them did (via symbiosis to their Elderlings and the links being powerful), I'm not so sure EVERY dragon had an Elderling. Icefyre is a good example, there. He roamed the world for a long time looking for other dragons before he went to sleep in the ice. And I believe Tintaglia mentions from time to time those dragons that wouldn't get close to humans.

I always supposed it was just a scientific thing. Just like in Earth's history when there have been supermassive volcanos which erupted and killed off most of the worlds living things due to the sky of ash, so too did this major cataclysmic event wipe out the majority of living things in the RotE.