The stated reason for the regressive curve was to:
The scenario that it seeks to combat is a single entity spreading their stake over many small accounts in order to hide their actions in noise.
Source
In practice, it was to combat bidbots, self-voting and other selfish behaviour from escaping detection, so they would be more visible to the stakeholders for downvoting.
But yes, of course, it goes against the minnows. My vote went down from $0.02 to $0.00.
That's my whole issue though. The underlying concept of stake-weighted voting is fundamentally flawed. Some things get better, others get worse, with every update. It might be a marginal improvement every time, but it's simply not enough. It's the definition of insanity to try small changes 21 (well, not really 21, but you know what I mean) different times but refuse to acknowledge and fix the actual problem once and for all. We need a radical new solution.
Sybil attack is real though. Dan introduced voice with the requirement for users to kyc themselves. That's no option imo.
Maybe I've been blind to it, but the problem with small accounts hiding in the noise didn't seem so big to me to shoot all minnows to solve it.
I agree, it does seem like an anti-social move to throw minnows under the bus.
And yes, sibyl attack is real. Dan's solution is KYC, Ned's solution was SMT + oracles. I hope someone comes up with a better solution. Giving the rich all the power is not the solution.