Having to fully complete the valencia 2 questline makes the materials for these things so far out of the way that no one bothers to get them unless they're either desperate, or bored with nothing better to do. And the materials together cost about 90m more than what the crystal is worth so no one sells them outright. If one breaks you'll probably be waiting like a week or so for an awakened spirit crystal to drop on the market. The black and awakened spirit should be moved to be mediah quest rewards since that's the last main quest that season requires. Or they could be added to the mountain of eternal winter quest rewards. 

This crystal is the best example of why crystals should not disappear after death.

It's available only once from the main quest. If someone completes the main plot only once and loses crystal, theoretically, they cannot get it back if everyone played the same.

Crystals should be harder to get but indestructible. Period.

Agreed.  These crystals are way too difficult to get for something that breaks.  Easier questlines or not making them breakable, I'll take either one.

+1