A lot of traders bought Luna when its price was very low and now they have millions of coins that were purchased for $20. And now the natural desire of such holders is for the coin to return to the previous price and they get a profit of hundreds of thousands, or maybe even millions of dollars. But these are just dreams)
The proposal sucks because they only have one snapshot for pre-attack, another snapshot for post-attack. There are lot of division and loses for their investors in between pre and post attacks.
There is a simulator for airdrop estimation and if you look at it, the airdropped is terrible. Not yet including vesting and cliff time.
https://terrarity.io/luna-airdrop