I may be misunderstanding their new fees, but this still feels like a major disincentive for using Unity. Even with revenue sharing instead of per-install fees, it is still being sprung on all the developers. Unity is now being upfront about not needing to use the newer Unity versions; but if there are engine bugs in the older versions, there is not much choice in if they have to update.
I would certainly think twice before choosing Unity at this point.