[Suzerain of Sheol]

Heh, indeed. And, also, it is possible they were like that given the... distant way that the Silmarillion is written. Tra-la-la-ing isn't something the narrator of that book is like to focus on.

One can imagine the elves awakening for the first time under the stars were probably pretty carefree. It's just, the Silm. has such an aura of despondency and lofty stoicism permeating the writing, it's hard to imagine that happening when you read it.