I hope this doesn't seem abrupt, and when/if it does, that it comes across as coming from a place inviting further discussion and appreciating your curiosity.
That's one of the effects of the pitch framing by Sabine: the design intent is not about smashing stuff at higher energy, despite the basis of the critique requiring that it is.
My comment above is really long, but tl;dr the impetus for both facilities is smashing electrons and positrons and specific features of those collisions that let physicists hone in on the discoveries made at the LHC, not moar energy leading to new particle observations that theory never predicted.
That's one of the effects of the pitch framing by Sabine: the design intent is not about smashing stuff at higher energy, despite the basis of the critique requiring that it is.
My comment above is really long, but tl;dr the impetus for both facilities is smashing electrons and positrons and specific features of those collisions that let physicists hone in on the discoveries made at the LHC, not moar energy leading to new particle observations that theory never predicted.