How could they not? since they are entrenched in the PoW mindset, and is confrontational when even someone mentions PoS. But the reality has PROVEN, that PoS is more secure and more community friendly (due to not having to transfer value out of the eco-system).
what proof do you speak of?
1. Many PoW altcoin has been 51% attacked, to the point the Dev just given up fighting back. Zero PoS altcoin has been successfully attacked so far.
2. In the altcoin competition, the PoS eco-systems has naturally risen to the top, on coinmarketcap right now, #4,#6,#7 are PoS, and #10 is a subsidiary of #4.
#1 Bitcoin, #3 Litecoin has early mover advantage, #2 Ripple is a scam that is non-PoW and non-PoS. I expect Litecoin will soon lose to a PoS eco-system in less than a year.
If Bitcoin keeps PoW, it'll be next, in 3-4 years time probably. This is because PoS re-invest in the community and eco-system, PoW transfers value out of the community and eco-system, into the pockets of hardware vendor/electric company.
Proof of Stakes rely on central checkpointing, (and therefore aren't
distributed. ) And they are vulnerable to nothing at stake
attacks.
Perhaps PoS haven't been successfully attacked but
I don't believe it is scalable.
Nope, just the contrary, PoW relies on centralized checkpointing, Bitcoin has checkpointing. PoS does not need centralized checkpointing because it's so hard to attack it, Peercoin is now fading out the checkpointing, because PoS has taken over the network, and PoW is fading out. BitsharesX, a pure PoS system, has no checkpointing.
NAS attack against a PoS system is pretty much fictional. When I asked why it haven't happened yet in reality, Gavin's reply was basically "people might not have figured out a good way to attack or built the tools to attack it yet". Well I'll believe it when I see it, so far I haven't seen it happen in reality, though you are welcome to change my mind, go initiate a NAS attack on a PoS system, see how far you could get.
I could attack any smaller PoW altcoin right now, with just a handful of ASIC machines. The weakness of PoW security is PROVEN, and exists in reality. All the PoS attack theories are UNPROVEN, and doesn't exist in reality.
So I'm not sure why Bitcoin is sticking to a proven insecure system, with $500 million current annual expense. But not adopt a system that have no security issue in reality, and has nearly no expense.
Believe whatever you want to believe. NaS makes sense to me. I can see how its a problem.
"I'll believe it when I see it" applies to me too. When a PoS coin overtakes Bitcoin, let me know.
Later.