When you clone a repo from Github, you now have locally an equally as valid and complete repository as Github. If you expose access to it over the Internet, I could clone that repo from you, work on it, and send patches to you. Etc.
Git was designed to facilitate a network of repos. For better or worse, most use cases naturally gravitate towards a single clone as the "canonical version", and unfortunately we've all got too comfortable in having that version be owned by a third party service provider.
Legitimate question, as most people see this as hosted on a server somewhere and your client doesn't sync with other clients... usually!
You do, in fact, have a client capable of working without a central server. It's tedious but sending patches over email is definitely one way to make it work without relying on a single system. You can also have and push to or fetch from multiple servers with your client, which can be other developer's own servers, or a server reachable over Tor as a hidden service, etc. It's very flexible if you want to go that path.
git was designed to be used decentrally. Every clone of a git repo is technically an equally valid source of truth for the repository. In practice though, pretty much every project has a single git repo that is used to synchronize all the other copies of the repo, because it's much easier to coordinate.
When people say decentralized they mean something like bittorrent or ipfs, often as opposed to http. Saying http is decentralized is... stretching the definition. With this logic a USB cable is decentralized because "you can use it against any target you like". USB mass storage dead drop devices can be connected to by anyone. And USB "is a protocol", just like the examples you mentioned. But I doubt anyone would claim USB is decentralized.
Though git is also not really what people would usually mean by decentralized (as it doesn't, by itself, try to connect to a pool of servers, DHT network, or something like that), it's definitely closer to it than http.
I'm also not sure "for real?" helps the conversation.
> having at least some of the processing done by the individual workstations and having information shared by and often stored at the workstations
Decentralized:
> the dispersion or distribution of functions and powers
(Both from Merriam Webster)
BitTorrent definitely fits the distributed definition (as you said), but whether HTTP is decentralized depends on how you view it. Yes, there can be more than one HTTP server, but again, there is more than one USB cable and I wouldn't call that decentralized. HTTP doesn't distribute the functions and powers between the client and the server (the two parties in any HTTP request): the client can hardly serve the response and the server can hardly issue a request. But it does distribute functions and powers between multiple servers because there isn't one global HTTP server or party that serves the Internet (now that would be a scary thought--looking at you, CloudFlare).
So it depends a bit on the explanation of that definition.
I think what I said before might be right: it's "stretching" the definition (interpreting it in a way that includes this). I can certainly see where you're coming from (anyone can host their own HTTP server just like anyone can host their own email or git server or bittorrent node) but it's not really how the word is usually used. But perhaps we use it wrong, because it does seem like a useful distinction to make (a centralized (proprietary) game server vs. a decentralized protocol like HTTP vs. a distributed protocol like BitTorrent).
It would be terrible if youtube-dl.com would digitally sign and release youtube-dl source as zips on thepiratebay and other torrenting sites instead of github.com.
