You won't remember this but Hopkins turn down a Toney fight way before Oscar agree to fight Hopkins. Remember Hopkins refuse to fight Toney before Hopkins fought Hakker or Joppy so theres no way Oscar agree to fight Hopkins in that moment.
Probably because its a distinctly uninteresting fight. Simple as that. It has no fanfare, its pretty meaningless in comparison to a fight with Chad Dawson or Adamek who are champions of their divisions, I don't see any great money in it. There is just nothing in it. It's 10 years too late.
The catchweight would have to be 210lbs, Toney can not possibly get lighter than that anymore, and he would have a hard enough time getting there in the first place. And if he does it right it would take him at least another 6 months. I don't see B-Hop having too much trouble bulking up to 200lbs, where he could face Toney at HW and then move back to CW wothout a problem. But imo Toney should just try and chase one more big fight at HW, maybe a title-shot.
Both Hopkins and Toney are still big names and a fight with them would be highly marketable and bring enough $$. They could market it as a 'real old-school fight' or something like that. For boxing, it would be no less relevant than Hopkins-Jones II these days (which isn't much). That said, I don't think they should make that fight.