Proof of stake coins are the ones that will allow you to earn passively. So, it's like an interest that you'll earn which is called APY that you'll earn a percentage annually.
Exchanges do offer this but there's the risk on it because you are not the one who's holding the key.
Sure, if you wanna call a coin decreasing in value by half every year but giving you 17% APY
”passive income” then go ahead and call it that way, but I’m quite less than 10% of the staking tokens actually overperform their own inflation lol. Then if you take a chart of that token against BTC you’ll see it’s only losing value constantly.
Well, that's the counterpart on these staking coins. You can't expect majority of them to perform very well and if there are some that really does then that's good but won't be the same the next months or year.
Another one is the decreasing APY that it gives, while it's still fresh the APY that they'll give is quite high but it's not permanent and will change over time when there are more people that does stake it.
On this thing, it's not that really sustainable at all with high percentages and that's why we see most of them drop their rates.