Any new open source software is always a net positive.
But, there are a few small caveats to the way they’ve done it (depending on how cynical/cautious you are):
Because Proton are not accepting contributions, they own all the copyright, so can make the code closed source again if they want to (that wouldn’t affect the already released versions, but future versions)
They could likely take down any derivative on iOS, since Apple will always take instruction from the copyright holder, for GPL’d code
Since the builds are not reproducible, there’s no guarantee that the binaries they distribute are built from the source code
It means it can’t ever become proprietary closed-source software (not without a major lawsuit).
Any new open source software is always a net positive.
But, there are a few small caveats to the way they’ve done it (depending on how cynical/cautious you are):
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Any GPL violations would be reported to the Software Freedom Conservacy, who would go to court on the dev’s behalf.
There was a major lawsuit back in 2022 between the SFC and Vizio, and the SFC won.
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