I think this strategy or step is not right, Move all altcoins to Bitcoin. Actually it's good if you want to have bitcoin assets, but it's better to share a few percent for altcoins and the rest for Bitcoin. If for all, it might be profitable and even possible to suffer losses.
I agree that we should keep a certain amount of Bitcoin, but should not completely hold 100% Bitcoin, there are still a lot of good coins out there. Normally I do not keep the amount of Bitcoin exceeding 50% of my assets, the rest I will invest in potential altcoin.