Earlier quoted context omitted.
There are some things you simply can't do on GitHub: * block trolls from interacting with an organization, short of filing a support ticket * install pre-receive hooks without using the pull request infrastructure * set up status checks (the PR equivalent of pre-receive hooks) for pull requests that require force pushes, allowing some external check to replace git's usual fast-forward check * have status checks apply…
Something else that's IMO more important than any of those items is this: You can't submit patches. Submitting/accepting a patch is something that straight up cannot be done on GitHub. Unless you use a sidechannel like sending a message containing a link to a patch that you threw up on some host somewhere (in which case, have fun rooting out that information on a case-by-case basis), the only way to ever get any chan…
It is true that the inability to submit a PR without a local clone is annoying. For the use case you describe, a one-line fix, note that GitHub has a web-based editor (that will create a fork if necessary), so you can skip the local branch entirely.
Someone could probably toss together a web service that does the equivalent of a `git clone --depth 1` behind the scenes and then applies your patch.