Backed five years ago, looking for a TLDR of where we're at now :)

Nothing's playable now.

Alpha-2 is meant to give at least the base of multiple systems and will be playable next but has no known 'due date'.

If we assume that Alpha-1 was entirely subject to change and is undergoing a full change and revamp, we do not have information on Archetypes, Classes, Abilities, Weapons, or Combat systems.

We have multiple 'confirmations' of continuing with intended systems, theme, and similar.

Scope is not changed significantly. Nodes were working decently in Alpha-1 last year, and are being expanded now. New biomes have been seen.

Game appears to be on track for most core goals of Alpha-2, as of now.

Alpha-1 went well.

Even still, it's good to be cautious about one's expectations of persistence. The purpose of Alphas (and even Betas, though the context is different) is to find bugs and work through any unexpected issues that may come up. I have no doubt that the team will try to aim for persistence (they even did this to a limited degree in Alpha 1, when they had made no promise to), it's not unreasonable to expect that there may be some resets from time to time as things develop.