Prior to SpaceX disrupting the market by surprisingly making what was widely regarded as a bad idea actually work, this was the way to go and I would be surprised, maybe angry, if a government backed effort went with a very costly high-risk/high-return project.
A bit like the Alcubierre-White warp drive: I'm fine with a relatively small budget funding research on it, but no sane person would approve "investing" one SLS worth of money in that.
I have no doubt Ariane 7 will be reusable.