From a theoretical standpoint, this answer could get very long, but the real answer boils down to the creator of the protocol prefers bitcoin.
On the theoretical side, I'd argue that bitcoin PoW is the best choice because it is more resistant to malicious actors. Assuming that a solution to the botting issue requires a small proof-of-work or fee to post, on a PoW chain malicious actors would need to control a large amount of energy inflow and hash power to support their botting operation. Whereas on a PoS chain, they simply needs a large pool of capital to be staked, which would give returns that can support their operation. This means that the attack vector is larger on a PoS chain than a PoW chain. This is also why the nostr protocol itself has a proof-of-work component. It's the simplest solution to two-generals problem.
Proof of work also depends on capital, compute isn't free. In fact, it is already incredibly centralized in the Bitcoin blockchain because there's like 3 big players which have already attacked the Bitcoin Cash blockchain. The only reason these huge pools haven't attacked the Bitcoin blockchain is because they have a financial stake on the price being high, which is also the same incentive proof of stake depends on.
Ethereum’s recent move to Proof of Stake undermines the their ability to be decentralized and permission-less. If a validator adds a blacklisted transaction, they will be slashed [0].
Ethereum had an unfair issuance. That means the founders kept a pool of coins for themselves and have unfair control of the network, furthered by PoS.
Ethereum is effectively a private tech company led by a CEO. They have a public roadmap.
Ultimately I think these fundamental properties of Ethereum make it inadequate as a permission-less money protocol. It works great for games and apps, but its foundations are susceptible to coercion and control - and you can’t build a permission-less protocol on that foundation.
No, your link shows that a majority of validators will not include certain transactions in a block. While problematic in itself, there is nothing around slashing other validators who do so, on their allotted blocks.
Technically you can still obtain 32 ETH on the market, permissionlessly set up your own beacon-, validator- and execution clients and wait until it's your go to send out txes.
I think someone did some monero focused client and relay implementation. Go on and create your own nostr eth implementation. Maybe even try to submit a NIP for this.
On the theoretical side, I'd argue that bitcoin PoW is the best choice because it is more resistant to malicious actors. Assuming that a solution to the botting issue requires a small proof-of-work or fee to post, on a PoW chain malicious actors would need to control a large amount of energy inflow and hash power to support their botting operation. Whereas on a PoS chain, they simply needs a large pool of capital to be staked, which would give returns that can support their operation. This means that the attack vector is larger on a PoS chain than a PoW chain. This is also why the nostr protocol itself has a proof-of-work component. It's the simplest solution to two-generals problem.