You own sentence shows the relevant difference: "embedded". The GPL license has always stopped at the OS process boundary. You can essentially do whatever you want with a GPL program as long as you interact with it over standard OS mechanisms, rather than direct modification; you're still obligated to distribute source but it's source that is already publicly available, so there's no proprietary interest in it. Mongo's does not. Neither does the AGPL, to show this isn't new.
> The GPL license has always stopped at the OS process boundary. You can essentially do whatever you want with a GPL program as long as you interact with it over standard OS mechanisms, rather than direct modification
Not strictly the case according to the FSF's FAQ; the GPL applies to anything that integrates deeply enough with the covered program to constitute a "derivative work" under copyright law, which is not necessarily the process boundary.
> Neither does the AGPL, to show this isn't new.
Indeed - so what is RedHat's rationale for permitting AGPL but disallowing this MongoDB license?
> The GPL license has always stopped at the OS process boundary
No, it stops at the copyright law boundary of derivative work.
Whether or not a court would find that to be equivalent to an OS process boundary probably varies by jurisdiction and detailed facts of particular cases.
