I'd say that most people don't downvote a whale self-voting because they don't want their own posts to be revenge-downvoted.

Yep, it is self-preservation and there is no incentive for anyone else to get involved.

My hope is that these potential changes, downvotes become a lot more common and the perception changes from a feeling of being personally attacked to an indication that the platform doesn't think the content and rewards line up.

I hope this too.

I think these sorts of changes could improve the quality overall... so that's exciting

At the very least, it opens up more games to play :D