Consider the following scenario
- Project A is originally licensed under a permissive license
- By the time it reaches version 6, it has built up a strong user base, many of those users producing closed commercial products.
- The original copyright holders decide that version 7 should be licensed under a copyleft license.
- This decision means that the commercial companies will not use version 7 for fear of being forced to disclose some IP they want to keep private (regardless of any realities).
At this point, someone forks version 6, retaining the original license. They continue to develop it into a competing project which picks up all the old commercial customers (and possibly their funding and technical contributors and other resources).
All this is allowed by the original license: but it clearly subverts the intent of the original copyright holders expressed in their decision to relicense.
Is this a natural consequence/risk of initially choosing a permissive license? Is this a problem, or a benefit?