That's the problem with tail risks. How do you know what is a "long enough time?"
This is why the catastrophic failure issue suggests there shouldn't really be one coin after all, and trying to maximize "network effect" may be over-fitting. Monoculture is fragile.
By that I meant long enough to see some of the tail risks manifest, and to see the recovery from it (if it does). We identified some pernicious ones already.
There is a lot of talk about what "will" happen, but if we are honest with ourselves, we don't know what will happen.
Let's game this out. Is a year long enough? Two years? Three years? Twenty years? How can you even know that tail risks don't remain?
I don't think it is possible.