I added this after: Or maybe is the argument that... yes you could build a side chain that could confuse nodes up to a certain time, but that side chain will never catch up to the work added to the main chain?
So I suppose now if I am understanding the argument correctly is that.. sure you can alter the timestamps and perhaps make a confusing fork on a PoW coin, but at the end of the day it is going to be pretty much impossible to be able to have a chain that ends with the same level of computation that the main chain has.
On the other hand, using PoS, and supposing that there are no checkpoints... it would be possible to re-mine and restake all the way from the genesis block and and result in a chain that has higher trust than the main chain.
Congratulations for realizing what all of us had realized.
Don't know what the hostility is for... Superiority complex I suppose.
So I guess my conclusion here would be, so long as there are hard checkpoints set into proof of stake chains after the coin has been widely distributed to many different individuals, and such that it turns into a proof-of-working-stake style coin, then there should not be any risk. At such a point it is not feasible to get enough coinage to launch an attack that would build a larger trust score.
Of course thats just my opinion. And I am not here to be in a PoS is better than PoW argument. PoW that has significant hash power is that is widely distributed (ie not a few pools running the show) would probably be the safest system IMO. But at the end of the day, PoS is easy to use and you don't need to buy equipment from a select few group of companies that produce that equipment.