At any point, if interest rates aren't pretty much exactly zero, it pays to delay burying waste. The present cost of guarding it at the surface is < the cost of burying it now. If, at any time, the interest rates do drop to zero and stay there, it can be buried then.
The only real argument against this is that the waste ceases to be self-protecting from "amateur" diversion of plutonium in about 300 years, which could greatly increase the cost of guarding. But that's no justification for burying it now.
Waiting also reduces the thermal output from fission products, which reduces heat buildup in the repository, at least a bit. And it would allow the waste to be reprocessed (and more easily) if that (perhaps unexpectedly) becomes appropriate. It would also allow time for other disposal methods, such as launching into space, to become competitive. How cheap will the descendants of SpaceX's launchers be in 300 years?
I think there may have been an argument for rapidly burying waste during the cold war, where surface waste could be volatilized by a direct H bomb strike, causing enhanced local long term fallout. That's more an argument against nuclear power itself, though, as NPPs could also be disrupted by direct strikes.
This is always a funny topic when people wax philosophical about dirty bombs as though you wouldn't get cooked trying to open a cask.
This attitude only makes sense if one's view is that humanity isn't going to last more than 10,000 years.
Unless we can find a way of rendering nuclear waste safe, then we have to find a way of making it so inaccessible that a future civilisation is unlikely to come across it by accident, and so secure that even a major earthquake won't cause it to leak into the environment.
Storing this stuff in metal tins on the surface isn't even a gesture at a solution.