> physicists say it’s a reasonable assumption that there might not be anything new to find until energy scales of 100,000,000 TeV or more
This is an extremely pessimistic view. Yes, we're almost certainly going to find something there, but that doesn't mean there's nothing before then. I'd bet a reasonably large sum of money that there's something before around 10TeV.
Also, this collider isn't looking for new particles so much as trying to improve our understanding of ones we know about already.
