Where is censorship resistance when the on ramps and stakers become centralized?
However both can be overcome by pooling money or hash power...but then again that doesn't lead to more decentralization.
While pooling hashpower doesn't solve the economies of scale mentioned above. If your hashrate per kW is bad you will get a very poor yield on your investment. There is also a commission to pay to the pool operator. Pooling in PoW serves only to receive a more consistent revenue stream.
If the pool operators don't actually own the mining hardware then their power is limited to what the participants in the pool, who do own the hardware, allow them to do. If as an individual miner you don't like what your pool operator is doing you can always switch to another pool and take your delegated influence with you. Most proposals require supporting votes in many blocks before they take effect, so you have time to choose a more representative operator.
That's to me similar, if not worse than with PoW.
- Fixed costs that act as barrier of entry
- Economies of scale that lead to centralization
- Geographic factors (operation costs being different in different parts of the world, regulation/taxation, supply chain...)
This is how I see each factor playing out in both scenarios:
- Fixed costs: PoS runs on consumer-grade hardware, while PoW requires specific HW (ASICs or high-grade GPUs). PoS requires a minimum amount of stake but there are pooling solutions, which effectively make this minimum non existent. All in all PoS is at advantage here, unless you want to insist on solo staking in which case PoW is at advantage.
Analogy: This would be equivalent to flat fees to open a savings account or a minimum amount balance required to open it.
- Economies of scale: In PoS they are almost non-existent. You don't stake more efficiently by having a more powerful machine. You just get to reuse the same HW for more nodes but since fixed costs are low this has a very small impact. In PoW there are economies of scale, though, better/more expensive ASICs can mine more efficiently than smaller/cheaper ones. Same with GPUs. Someone with more initial capital can get ahead faster in PoW, while in PoS earns at a same rate as everyone else.
Analogy: This would be equivalent to the interest rate you get in your savings account being dependent on how much money you have. In PoW, the richer you are the higher interest rate you get from your bank, in PoS everyone gets the same.
- Geographic factors: Cheap access to energy has a large impact on PoW as it dictates most of your OpEx. In PoS this is largely irrelevant (PoS is 99.95% more energy efficient than PoW). Taxation/regulation would need its own analysis but I imagine is equally spread across both alternatives. Supply chain is again in favor of PoS as it can run on general-purpose HW, while ASICs are heavily centralized around a single manufacturer.
Analogy: This would be equivalent to different geographic locations resulting in different conditions for maintaining open your bank account or taxing your accrued interest.