It looks like it is, but is there any official word that the SSPL is proprietary? As far as I know MongoDB claims it isn't, and it hasn't been reviewed officially by either the FSF or the OSI. Is it in license purgatory?
The reaction on the OSI's license-review list is more varied. Lawrence Rosen and Ken Mitchell argue that the license should be approved. Everyone else is criticizing that it clearly violates the spirit of Open Source software (no discrimination against fields of endeavour!), and that the license is too broad and too vague in the critical section (Rosen agrees with the latter part). Carlo Piana points out that the goal of the license seems to be to create so much legal uncertainty that any serious user would be forced to buy a proprietary license from MongoDB.
Here's me announcing an attempt at a plain-language, SSPL-style license from scratch:
https://writing.kemitchell.com/2019/01/12/Shared-Component-L...
The latest license text is at:
In particular it requires you to license "the Corresponding Source for all programs that you use to make the Program or modified version available as a service" under the SSPL. That naturally includes the linux kernel which is licensed under the GPL - and cannot be simply relicensed.
E.g. I could make a license exactly like the GPL except with a clause saying fuzzy2 on HN can't use my software without paying me.
Even though RedHat and Debian aren't fuzzy2 on HN, and 99.99...% (or 100%) of their users aren't that user either, they'd still refuse to distribute it. That license would be non-free.
Edit: Usually don't complain about down votes, but I'd be happy to hear why the parent is incorrect if I've got it wrong. Are they not legally able to distribute for some reason?
Re-Edit: I read the initial query incorrectly. Yes, the parent's post is unrelated to the query. Sorry!
They still usually don't, because it would break the automatically trouble-free property of their distribution. If users have to check the license of software before using them, there is little point in packaging all of it together and automatically installing, so there is little point on making a distro at all.