It's been said that the "GitHub generation" of developers cares more about the practical aspects of openness than rigid definitions. I'm not of that generation, but I enjoy watching these battles from the sidelines. Don't contribute to any software where there's a risk the stewards will licence switch on you. Or do, if you need to get a fix upstream and it's the most expedient solution. It's a business decision like many other we need to make.
> Don't contribute to any software where there's a risk the stewards will licence switch on you
If you contribute, you own copyright to your contribution and the software can't be relicensed without your approval (or removal/reimplementation of the parts you added).
The trick is to not grant the copyright assignment (ie. gift the maintainers your copyright).
As an example, here's what MongoDBs contributor agreement[0] says:
> By submitting a contribution, you assign to MongoDB all right, title and interest in any copright you have in the Contribution, and you wave any rifghts, including any moral rights, database rights, etc. that may affect our ownership of the copyright in the Contribution.
Other projects have similar language. If you contribute a project and sign something like that, you're not contributing to an open source project[1] - you're working for that corporation for free.
They can only change the license of future contributions alone.
Your contributions are still protected by your original license, unless you agreed to some other license in parallel (such as via a contributor agreement).
Therefore, by including your work without respecting the terms of your license (such as the MIT license text inclusion), they are violating your copyright.
As such, any contributor agreement should make you think twice.
