> The only up side is that the decay products have a shorter half life. So the waste will only be a problem for a century or so, instead of for millennia.
This sounds like a tremendous underestimation of the problem - handling waste.
We have people who live 'for a century or so' but we don't even have languages (now!) that have lasted a millenia.
Our current "decay product" of energy generation (carbon) is going to impact our world for a lot longer than a century. I'll take known-quantity, manageable century-long decay products over unknown-quantity, nearly unmanageable (large-scale carbon sequestration is hard) any day.
You might make the case that MSA and Classical Arabic is an exception, but MSA is not spoken natively AFAIK. Other than that, I cannot think of any examples where a language spoken by someone a thousand years ago would be intelligible now. Languages change in sound, structure and vocabulary over time naturally. That's how we got the Romance languages from Latin (which is no longer spoken).
However, language standardization artificially slows down change, so current languages might last a lot longer. English hasn't changed that much since Shakespeare and the KJV.
Maybe interesting to you: https://en.m.wikipedia.org/w/index.php?title=Conservative_(l...
Yes, for written form you could make that argument, though there are some differences between the two. Also, it didn't really "last" in the normal sense, since it was revived in modern times.
Also, Tibetan maintains the same spellings from 1200 years ago, but that really just means that it's very, very difficult to spell, since the pronunciation no longer matches spelling well.
These make interesting exceptions to the general rule, so I think the original point is still very valid. I'm curious about old vs. modern Syrian, if anyone knows about that.
Okay, point taken - we certainly do have some languages still in use that that have lasted more than a millennia.
I'd posit that storage is not a solved problem, and a big part of that is a lack of confidence that we can reliably communicate with the people who will have to deal with this waste in the distant future.
There's also the inherent disdain involved in passing on massive costs and risks to future generations to solve a comparatively short-term problem of ours.
We have people who live 'for a century or so' but we don't even have languages (now!) that have lasted a millenia.