The solution isn't to make licenses more "user-friendly". That user friendliness can be a dangerous illusion. The solution is to not forget the legal lessons that we already lived back before free software was renamed to open source in 1998.
But they still remain with the problem that most folks choose the user-friendly MIT (I would, and 9 out of 10 of the top projects do). This leaves them with an issue: It's not clear that contributions submitted to an MIT project grant permission to incorporate those contributions under the same terms. We understand it socially, but it's not legally explicit.
Github has been trying to address this in their Terms of Service, by saying that simply by using the site, you agree that "inbound=outbound": https://help.github.com/articles/github-terms-of-service/#6-...
But the Github TOS isn't really the right place to be legislating that. For more, see: https://writing.kemitchell.com/2017/02/16/Against-Legislatin...
Given that GitHub works only through forks and pull requests, this is not a problem. There are two repos A and B published under the MIT License. There is no need to address what happens when the contributor behind B sends you a pull request. (There is no need for contributor who published B to even send you a pull request; in theory, you could "reach over" and start incorporating anything from B into A without any participation from the person behind B—just like you [probably] did with all your vendored libraries.)
Worrying about this is one of the cargo cultiest memes, second only to all the videos on YouTube who think they're protected by a notice that says, "I don't claim ownership of this video; all rights belong to X".
That's an interesting reading of history, and one that the creators of the terms "free software" and "open source" would probably both vigorously dispute.
http://jordi.inversethought.com/blog/5-things-we-have-forgot...
And here:
1996:
https://groups.google.com/d/msg/no.linux/1UZo-3iv0tM/XPrPljd...
1995:
https://groups.google.com/d/msg/comp.graphics.raytracing/6oZ...
While it sounds pretty brain-dead to put "open" in front of anything, to the point that it seems like the most natural thing for it, most people did not use this term and there was very little widespread understanding of what "open source" meant. If it wasn't for OSI, we'd still be saying a bunch of disjointed things instead of being universally aware of something called "open source".
Every time I have this discussion, someone comes along and thinks, "wait a minute, there's no way that OSI coined that term", but yes, they did. This is probably a Mandela effect.
https://www.gnu.org/philosophy/open-source-misses-the-point....
And especially:
"The two terms describe almost the same category of software, but they stand for views based on fundamentally different values. Open source is a development methodology; free software is a social movement.... Most discussion of 'open source' pays no attention to right and wrong, only to popularity and success..."
And of course OSI officially wrote "We realized it was time to dump the confrontational attitude that has been associated with 'free software' in the past and sell the idea strictly on the same pragmatic, business-case grounds that motivated Netscape." (http://web.archive.org/web/19981206185148/http://www.opensou...)
In other words, "open source" was about depoliticizing "free software" to make it more commercially palatable. (And arguably, it worked.)
Kind of like machine learning instead of statistics.
You can also see this in the evolution of several licenses that have gone through more than one version. While I really hate comparing software to licenses, think of those as "bugfixes" (or perhaps, warnings to others of bad example licenses). I already gave GPLv1 and the original Artistic License as what not to do; Apache v1 is another example because of patents.