https://coinmarketcap.com/charts/#dominance-percentageNot surprisingly enough, looks like altcoins lose dominance in times of uncertainty witih Bitcoin. So even if Bitcoin loses value against USD, it wins value against altcoins. This proves that when the shitcoin bubble pops, it's going to bring Bitcoin back to 80% average dominance (where it belongs). Very few altcoins are worth the risk of diversification hoping for some BTC gains, so if you can afford low risk, just say 100% on BTC, and things will sort itselves in the next 3 years.
When we are facing a bearish trend and then the majority of altcoin holders are converting their altcoin to the bitcoin, if we will be facing another bullish trend and they are repurchasing their altcoin again.
I'm not getting any surprise for that becuase this is an old scenario.
Well, I have heard that story both ways:
1) "When bitcoin goes down, people sell their altcoins for bitcoin"
and
2) "When bitcoin goes up, people sell their altcoins for bitcoin"
I have seen both scenarios play out, sometimes they apply and sometimes they don't.