Decentralization purism is like all purism. I do not think it desirable generally to use completely decentralized systems. These have the obvious advantage of structural durability, i.e. few points of failure and easy backup and reinitialization. But coordinated action and decision making requires a basic level of centralization to be efficient. The sultan protects merchant travelers entering his land and in the bazaar places his officer of weights and measures to police fair and free exchange in the marketplace.
suppose I piss in your punch...it's a BIG punch bowl...a few gallons...surely you wouldn't mind just a few ounces of piss?
are you a PURIST?
Relieve yourself up the river a few miles, I'll be fine.
near the feedlot?
((already not a purist))
Sure. Yet people are under the impression their creations cannot be censored because it is decentralized. If there is a centralized gateway that cannot be replicated by others and is controlled by a single entity then that censorship is still valid if say the entity stops following it's own motto like Google, or if the entity is just eliminated. Your data may still be out there in the blockchain, but if there is no ready way for other people to build something to access it then it might as well not be there.
As to purist. I am no purist in anything. I am a realist. :)
Depending upon what people's goals are they should understand the truth of the matter rather than working off assumptions that are wrong.
As to blockchain and decentralization PURITY. This is all new, there is no one alive that can know whether purity is desirable or not in it. Do you understand why? Because, it hasn't been done yet. It's too new.
It may be desirable in some implementations and not desirable in others. We truly do not know yet. Each foray into the field is like an explorer trying to reach a new land. We don't know if that land is a place we want to visit or not until after it has been found. Certainly once we set foot upon new shores we are going to meet challenges, we're going to have "this is great!" moments, as well as "This is bad!" moments and in many cases they will likely be things we didn't even anticipate.
The main reason it is difficult to be purist in decentralization is that a number of the services you wish to provide are VERY tricky to implement in a decentralized fashion. A purist would not use web pages at all and would create a new protocol designed to navigate the decentralization when displaying pages so pages could not be shut down easily by just shutting down one host they are running on, DDOs, etc. Yet since web pages rely on HTTP and HTTPS that by their nature are based around transactions with a specific IP address we don't have that. However, creating a new protocol, building browser support, and convincing the masses to adopt it does not seem very realistic. So the next best thing is having at least open source code so that ideally if one site goes down, people with the desire could bring up another accessing the same data.
From a philosophical standpoint purism is practicably unsound. I think a composite system is best, where there would be a high level of decentralization over the whole system but also a manner of centralization at certain fundamental nodes. At present we haven't quite yet the sophistication for sufficient technological decentralization, and we also haven't figured out the end goal of decentralizing our world. Where do you want us to head in this regard? I want enhanced (but maybe not maximal) sovereignty of individuals as citizens - I haven't thought much about this.
Actually the blog side of steem does it quite well.
All of the data is on the blockchain.
Which website you choose to view that data steemit.com, busy.org, esteem, dtube.video, dlive.io doesn't matter as long as they all tap into the same blockchain.
Once you choose a website which will always be centralized as long as we continue to use current http and https protocols for such things. However, if your code is open source, and that source can tap into the same data then it doesn't matter that it is centralized. If someone takes out steemit, dozens of people could bring up similar sites in a matter of hours using the source code. So this mitigates the vulnerability in a centralized system.
If you don't have that then it kind of defeats the purpose of being decentralized in the first place as if it goes through a single gate keeper that can be taken down and stop it all then you might as well not decentralize at all as it is far easier to develop these things centralized and if you have centralized points of failure that cannot be gotten around to access the data then it is stupid to decentralize... doesn't really have a purpose other than marketing gimmick.