There are a lot of industries that saw a boost in business during the shutdowns who have seen declines (maybe MOST of them) since things have opened back up. Facebook's market cap has been decimated by the decline. Zoom too. Uber, Netflix, Patreon, you name it. Zuck actually said, "We assumed usage patterns would keep going up" --
-- but why would anybody think that? It's crazy. The world changed, and it didn't change BACK. It changed AGAIN, to whatever the heck THIS is.
As one of the many folks who never gave a second's thought to the ukulele before things shut down, and in fact picked it up to deal with the added stress I was feeling (as much from my previous job as "all this", tbh), I'm very aware that there was a wave of us. Cynthia Lin nicknamed us "qukes" for quarantine ukers, and I both love and embrace that....but if some of the biggest, most valuable companies in the world got hammered when things changed AGAIN (rather than changed back), then how could a bunch of tiny instrument companies avoid it?
Additionally, supply of raw materials got tighter during shutdown, then once builders could get supplies, they ramped up production to meet demand, which then promptly dropped. Ouch!
A lot of what we're seeing in the Marketplace is its own version of market correction: "Uhm, I have too many ukuleles." Yeah, you and Kamaka.

I suspect a lot more folks than Kamaka feel into this dynamic, but I'm looking at the same sites y'all are, and it seems to have bit them harder than most.
I'm just guessing at all this, mind you, but looking across industries, the pattern is exactly the same, and, again, I don't see why we'd be exempt from it.
(This is probably a good time to remind y'all that I'm just talking here. I very much appreciate your gracious allowance of me speaking for myself sometimes without being the official voice of anything. In this, I am most surely not!)
Ohana is dealing with "all this" by opening a new custom shop to solve multiple problems at once: a smaller volume of built-to-order models at higher margins, that won't sit on shelves, and with a more local supply chain.
Kanile'a, confident in their supply chain and with a strong custom business already in place, moved
down into the open space in their product line between Islander and the K1 with the Oha series.
Pono and Anuenue both went upmarket. I was especially struck by the stock Koa Bird from Anuenue, built in Asia, costing MORE than Kanile'a's Hawaiian-built 25th anniversary model announced this weekend! There's obviously the 25th Anniversary Platinum Edition still out there, although Kanile'a's own allotment of them is sold out, but I still think it's gutsy to be this aggressive, just as I think it's gutsy of both Pono and Anuenue to not leave the high end to the K brands and luthiers.
The moral: the rules of the old normal no longer apply. Doing things the same way is a recipe for disaster.
I think we're a long way from it all shaking out, but I think it's a buyer's market for a while longer.