if usd collapses there will be a "nasa coin" a "virgina coin" an "ohio coin" etc. and they will likely be dominated by either the euro, russian rouble or the chinese yuan.
In other words, there is really no guarantee that if ever there can be collapse of the dollar that people will be moving to Bitcoin in a big way. I am sure that cryptocurrency and Bitcoin for that matter can be benefited but it does not mean that there will be an outright shift to Bitcoin. Why? When there can be a collapse people will really be afraid and since Bitcoin is quite volatile there can be no love on the first sight. This is the reason why there is a big need to make things better for Bitcoin right now so that in the eventually of an economic chaos in the USA it is already ready to take advantage of that development. I am hoping to be wrong though.