I don’t think 2.0 is an especially helpful term outside of the marketing sense of “OMG LOOK!1!! SOMETHING NEW!1!!”.
I’ve put my feelings on nomenclature here: https://hackmd.io/@polkadot/nomenclature
As it says, I’m not against having a version waypoint pre-JAM, but I’m not especially keen on calling that “2.0” and calling JAM “3.0” as it risks degrading the gravitas of the major version number months before we might wish to construe, outside of the ecosystem, the seriousness of the change.