those were sold out for months after launch
Yup.
A good part of that was the crypto bubble - everything and anything that was made sold instantly, at pretty much any price, because hey, free crypto money eventually pays for it, just a matter of how long you are willing to go out for an ROI.
By the time that had dried up, there was a lot of pent up demand and stuff kept clearing for a good bit. But eventually you have sold something to all the gamers that are able to continue to spend (nearly) anything just like the crypto guys, then the manufacturers have pulled the bottom end out of the market in the next generation. That means the rest of the modest-means gamers have had to just give up.
Now we've finally found the floor - those people who can afford cards; well that niche market did always exist, and they usually sprung for top-tier no-compromises models. And those have sold about as well as they always have. Everyone else looks for some spot on the value-proposition spectrum, and that's a bitter pill to swallow right now, as there isn't really any spectrum -- there's too expensive, too damned expensive, and holy F'n **** expensive.
I'm anxious to see what happens as the rest of this generation rolls out: we've already screwed the pooch near the high end, but we haven't seen what, if anything, they do towards the middle and bottom of the generational stack. Either side could right the ship if they bring some strong offerings in the sub-$500 market, and especially in that +/- $250 niche that has typically been the most popular.
All those gamers sitting with 1060's, 1050's, 1650's, and so forth are ready to upgrade (even if you believe that 90% of the SHS are game cafe machines over in Asia, those need upgrades too). They just need something in their price range worth upgrading to.