sorry didnt read your question fully
1) staking, theoretically adds stability to the network by contributing to price stability, it helps prevent massive crashes. so it encourages long term incentives
2) Aligns incentives through validators, because they also have skin in the game to make sure everything runs good while they have staked money.
3) it helps to prevent a 51% attack by introducing a poison pill. In a staked coin, the attacker needs 51% of the networks wealth. This inherently makes the attack cost prohibitive because as you buy, the price skyrockets, but if you hit 51% honest nodes will implement a slashing protocols to confiscate the coins. where as in non staked coins, the 51% attack is merely a function of compute power.
theres probably other reasons, but those are three big ones.
There is a fourth reason, and I think this often goes understated. But in privacy coins, being able to stake while maintaining total anonymity is massively beneficial. It allows black marketeers to stake portions of their wallet, while laundering other portions. So they no longer lose money due to inflation.