I’m not sure about the collateral part, but burning ICP seems like an idea worth considering.
The root cause of this problem is the fact that changing SNS parameters with the Manage Nervous System Parameters proposal topic is not considered a critical proposal. It means that the min and max dissolve delay can easily be changed and it can be done in a way that executes immediately without anyone having an opportunity to know or respond to the changes. I have been trying to raise this concern for quite some time now and so far DFINITY has not concluded that the SNS framework needs to changed to fix this vulnerability. My hope is that something will be done soon.
I started another thread that shows exactly how this threat was executed on the BoomDAO SNS already. Now it appears that a new principal has been used to attack as well. They probably used the exact same tactics. There is also an example of someone who has full control (critical majority) of another SNS treasury send ICP tokens form that treasury to his own wallet. In that case, it was written off by the community as fully legal and in the best interest of the community, which of course is a fallacy.
I agree with your basic premise here that something needs to be done to limit the changes that can be made to SNS projects to help protect them. I have even seen @borovan make comments to this effect, which I commend him for.