Given the recent hard fork proposal, I've noticed there are some complains about how increasing the block size means it would be cost prohibitive to run a full node, because of either storage or bandwidth issues.
However, I think that these people are complaining about a non problem. First, Satoshi himself stated that his vision of Bitcoin would be that as it becomes more popular and more widely used, most people would start to use SPV clients, and that full nodes and miners would only be available to few dedicated servers. So, Satoshi understood that decentralization doesn't mean that everyone can be a full node, but that everyone with the resources could become one, in the same way that in a free market, not everyone can sell products, but everyone with the resources and willing to invest can start to sell them.
Now, some people dislike when Satoshi is brought up because they feel it's an appeal to authority fallacy, and I agree with that. However, there are other arguments that support his idea.
I've said in another thread that the key to the success of humanity as species is specialization. Since the times of the first humans, there were hunters that went all day looking for animals to eat, and others who stayed at home taking care of the crops and the rest of the people such as kids.
As time progressed, humans have had more diverse and specific activities, I don't even know how many. For example, a student can choose to be an accountant, a graphic designer, an architect, a programmer, a civil engineer, a physicist, an entrepreneur, etc. They may choose not than one career, but trying to do all of them is unrealistic. Society works because there are people that know how to do one thing, but how to do it perfectly.
Another idea, already presented in other thread, is that not everything should be decentralized. Decentralization needs consensus of everyone involved for it to work, and as we've seen before, said consensus is quite difficult to obtain. Consensus also means that people understand the topic they're deciding about, which most of the time doesn't happen. People, as specialized as I've said, can only be expert in so many topics, and so expecting them to decide on everything turns out to be far from ideal, since they will choose what they think might work, it just choose what everybody else is choosing without even understanding what's going on. And this already happens with government elections. People sometimes vote for the most handsome candidate (and I've seen it, it's not a joke).
OK, so that's about consensus and specialization, but there's another issue here. Opponents of the fork argue that the new block size would severely limit access to the full node for those who can't afford larger bandwidth plans. But they somehow assume that the current software can be used by anyone in the world. To begin, around 40% of the world population has an internet connection today (
http://www.internetlivestats.com/internet-users/), which means that 60% just can't host a full node (how could they?). If you want to make the full node more inclusive, you need not to leave the limit at 1 MB, but actually decrease it to 0 MB so that everyone can participate (mathematically this makes sense, but it's obvious why this doesn't make sense). The other only option would be to give everyone Internet, but that it's tangential and not part of Bitcoin or Satoshi's plan.
Now, let's take the 40% that do have Internet. Can everyone have a full node? Should everyone? Well, no. Having a full node essentially means running a server (this was true even in 2009, but the servers were smaller). And running a server is not something everyone can do. We've talked about specialization before, and running a server requires knowledge of computers, networking, and protocols (in this case, the Bitcoin protocol). Someone that wants to run a full node either needs to already know about these concepts or be willing to learn about them. And then there's consensus.
Bitcoin is decentralized, so every time a new version is proposed, it means nothing until 95% of the network is willing to run it. Full node users must make the decision whether to do the upgrade or not, which ideally should be done if they are capable of taking that decision, not just leaving it to random chance or letting other people decide for them.
So, summarizing, why is the new block limit a bad idea? Because then not everyone could be able to run a full node? There are people right now who can't run it, and people willing to do it may not be prepared to deal with the responsibility of maintaining the server.
Let specialization do its work and allow anyone capable and with the resources to run the full nodes.
