Two architectures built against different constraints

A design that pushes throughput to the limit of a single machine pushes the requirement onto the machine. Solana's parallel runtime is described as using as many cores as are available to the validator, and the whitepaper's performance analysis is conducted on a stated network assumption and a stated hardware class. That is not a criticism; it is the direct consequence of choosing to scale vertically before scaling horizontally. The trade is explicit: the network gains throughput and pays for it in the cost of running a validating node.

Bitcoin's architecture makes the opposite trade. Its reference documentation describes a block as a structure whose serialised size is bounded by consensus, with the first transaction required to be a coinbase transaction paying the block reward. The bound is the point: a small block keeps the cost of validating the chain low enough that an ordinary participant can do it, which is what allows the security argument to rest on widespread independent validation rather than on a small set of well-funded operators. Bitcoin scales by keeping the base layer cheap to verify and pushing throughput elsewhere, which is why the layer-two and sidechain question is a live one for Bitcoin and not for Solana.

Neither choice is free. A high-throughput chain with demanding node requirements concentrates validation among operators who can afford the hardware, and the network's decentralisation is then a function of how many such operators exist and how independent they are. A low-throughput chain with cheap validation keeps the validator set broad and accepts that the base layer cannot carry the transaction volume of a global payment network. A reader comparing the two should decide which of those constraints they would rather live with, because the architectures are downstream of that decision.

The clearest way to compare the two is to ask what each network assumes about its participants. Bitcoin assumes that some participants are adversarial and that the honest majority is numerous and cheap to run, so the protocol is designed to be verifiable by anyone and to tolerate slow, deliberate change. Solana assumes that the network can be made fast enough that congestion is not the binding constraint, and it optimises the pipeline end to end, from transaction forwarding through execution to block propagation, on the premise that the leader schedule is known in advance and can be exploited.

That premise is visible in Gulf Stream, which forwards transactions to the expected leader ahead of time precisely because the leader schedule is deterministic. The documentation notes that this solution is not possible in networks with a non-deterministic leader schedule. Bitcoin's leader is chosen by the hash puzzle and is therefore unknown until a block is found, which is exactly why Bitcoin cannot adopt the same forwarding strategy and why its mempool behaves differently under load.

The honest summary is that the two networks are not ranked against each other by any single number. Solana's architecture delivers throughput that Bitcoin's does not attempt, at a node cost Bitcoin's does not impose. Bitcoin's architecture delivers a validation cost low enough for broad participation, at a throughput that requires other layers for anything beyond settlement. Which is better depends entirely on whether the application in front of you needs capacity or needs the cheapest possible independent verification.