When discussing the current crypto downturn in price, I think Terra Luna and TerraUSD should be excluded because what happened with this both projects is not like every normal crash but more of an attack on the project, who actually are those who attacked this project(s)?, I don't know but I believe we all know the story circulating around of what actually lead to the downturn of this both project.
So personally, I believe what happened with Luna and TerraUSD is something unique on its own, it's an attack and not just a normal crash that the crypto market in general is currently experiencing.
The project was a scam in the first place, a ticking bomb. Those who attacked it saw its weakness and exploited it to make some money, but by exposing it they potentially stopped many people from investing in this shitcoin.
You could say that exploiting a weakness in the coin is a bad thing, but they also showed what the plan of the Tera team was and what kind of people they were. They used trust that people had in Bitcoin to pump their own shitcoin. They not only lied about the amount of money they were planning to buy bitcoin with and really bought much less than they were bragging about, but also lied that this will make their stable coin backed by bitcoin.
In the real world their bitcoin was just lying there on a privately owned account and they were hoping that the purchase would not only pump Luna and increase trust in UST, but also pump BTC and make their holdings worth more. They were ready to dump BTC on the market and they did just that, only at a loss because the players got outplayed this time.