Max supply is infinite ..
This is not good. That explains why such high rewards.
No you are wrong.... If you have a PoS coin without infinite supply people would stop stakeing/ run MNs and network would die when block rewards stops.
most coins have finite supply thats what tends to give them more value, a pos coin can still have a finite amount just reduce the stake rewards so it takes years to get there, this instead is high interest that will pay out constantly causing the value to drop in the end as everyone has to many coins to sell, like a lot of the high interest mn coins released lately