> Same thing, isn't it? US dollar payments aren’t subject to the approval of stakers, and existing PoW miners have no on-chain mechanism to prevent new market

> Same thing, isn't it? US dollar payments aren’t subject to the approval of stakers, and existing PoW miners have no on-chain mechanism to prevent new market entrants from competing against them for hashrate. So, “no”. To begin staking, you first need stake. But merely transfering a PoS coin from an exchange to your own wallet for subsequent staking is inherently impossible without the approval of existing stakers. Even this isn’t enough: existing stakers must also approve of your initial staking transactions. Which is not how PoW mining works.