system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel's Defenders] (Spoilers) What would have happened if Davos had become the Iron Fist instead of Danny?

K'un Lun wouldn't have been left unguarded, that's for sure. Probably Danny would have still come back to the US to take his company back. The Hand would still have come looking for "The Substance," but Danny wouldn't be able to unlock the door. The Defenders wouldn't have an Iron Fist (although Danny is still an expert martial artist, so maybe he joins them anyway).

How would things have played out?
gpt
Danny leaving K'un Lun fucked up a bunch of things, but you've already pointed out the big two: the Hand wouldn't have been able to open the dragon's tomb, and K'un Lun wouldn't have been left unguarded when ... whatever happened, happened.

Without access to the tomb, the Hand slowly dies off. They'd still be an important political power for decades, maybe longer, but the five founding members would all succumb to mortality eventually, and the cult's devotion to them would end. They'd also run out of undead ninja zombies.

The Hand as a criminal organization is probably large enough to sustain itself without the founders, but they become more like any other cartel. Their leaders would be on the same level as Fisk, more or less.

We don't know what happened in K'un Lun, so we can't really say how having the Iron Fist there would have changed things. We do know, however, that Davos is a tiny bit unhinged, and his perception of what is right and good can be used against him. It isn't hard to imagine that whoever invaded K'un Lun would use his moral weaknesses to turn Davos against his masters. That might lead them to a supply of the Substance, and would also give an evil power access to the Iron Fist. 

That would probably become an Avengers-level threat quickly enough.