Unfortunately we have seen one of the biggest scam/failure of the project LUNA /UST where people have lost million/billions of dollars invested in them. We can't foresee such incidents but one thing is that if we follow the best practices of portfolio management, we could have minimize the loss.
No crypto assets in our portfolio should be that big, that in case of a mishap, our whole portfolio get a big hit. Also this means not to put all eggs in one basket in our crypto portfolio.
This is perhaps the biggest breakdown of crypto, we must not forget this valuable lesson. After all that happened, I hope everyone has come to their senses and should realize that there is no coin that can be more efficient and secure than bitcoin.
It is not necessary that we must and should only invest in bitcoin, we can still invest in altcoins but let's allocate capital properly and never invest all in altcoins because they are very risky. They can be profitable for us in the short term, but can also push us into the abyss in the same way that Luna did. My advice is to only invest in alt with no more than 20% of your capital. If you focus heavily on bitcoin, you will avoid the most pitfalls.