I wanted to support the question of runtime exceptions, quite an important point, so it’s appreciated that you intend to offer clarity here.
FWIW, the OpenModelica project, which has been mentioned above, uses such a licensing approach – the IDE/compiler are licensed (effectively) as AGPL, but any artifacts (read: compiled simulation models) it creates are under a runtime license (effectively: AGPL or BSD-New, at your choice). And in the past they specifically called out that their intention is to avoid people offering closed OpenModelica-as-a-Service, while they do not want to restrict the outputs that the users create.
In light of Julia’s maturing trimming feature and binary compilation, clarity on the license of the resulting binary seems quite relevant. Also for things like Dyad exporting FMUS.
Personally, as an acausal fluids-system person (so it looks like the MTKBase split will impact me), it will be good to know, as it impacts the relative attractiveness of Julia (which I’d like to use) vs. Modelica (which I do use), in practice, at work.
Also, a metadata-level (or other) flag as proposed above, to avoid unintentionally dragging in (A)GPL components sounds like a useful thing to ensure one stays compliant with the involved licenses. 