I know that personally, I've relicensed code to be more permissive on request. Of course, you have to ask, but sending an email might be less work than writing your own version.
I've done this twice with GPL code, when I was writing a library and/or library bindings that I specifically wanted to be available for use by all developers, including those working on proprietary products. Both times I've been turned down. One of them was a abandonware. Great C code that the author explicitly disowned. Now it will bitrot.
On the other hand, I have asked several developers who released code without a license if they would mind licensing their code under a permissive license, and each time they have been glad to do so.
The downside is, of course, that you probably need it at the time you come across it, so time wise I often have to roll my own in these cases. That’s why I hope this would make that more clear.
On that note, we need this for gists as well (maybe even more). Could be on an account-wide basis in my case.
Honestly, I don't know. I'd suppose it depends more on the sort of thing we're talking about than anything. If it's something like "Obtvse", or a fully formed system and you're copying it outwardly, then probably yes.
If it's a ilbrary that fetches RSS feeds as part of a larger system, I'm guessing no.
Of course, it also depends significantly on the author. If it's a public git repository, one assumes that it's something people wish to be forked.
Though I suppose an interesting experiment would be to publicly post closed source code with a closed source license attached as honeypots and sue everyone that forks / modifies your code base.
I suppose you could write a license that allows others to view and copy your code, but not make any modifications, as fork doesn't seem to be defined to include modification.
On the other hand, I have asked several developers who released code without a license if they would mind licensing their code under a permissive license, and each time they have been glad to do so.
Just some anecdotal data...