There is no necessary for all the altcoins to be bullish when the Bitcoin turns out to be bullish so keep holding until bullish or just buy Bitcoin.
We already know what led to the constant booming of these projects then which was the hype of ICO that was all over, but the ICO that did the magic is already phasing out now, so it’s time to just embrace the system new operating way now, which I believe it is this slow and steady pattern they will all use to reach their destination.