Is there any relationship between the two?
Whh must the fall of bitcoin after other altcoins?
The reason is that Bitcoin is where many people can easily access and it is the currency they can exchange to their local currency, so when the price drops it automatically affects altcoins because even the altcoins are also exchanged to bitcoin.
Those who fear will fomo according to the value of bitcoin, they worry that bitcoin may continue to decrease. So they sold their altcoin to bitcoin that reduced the altcoin, then they sold the bitcoin to usdt, causing the bitcoin to fall again.
the level of interest in this distant Bitcoin more than Altcoin making it the coin that became the first benchmark to generate even more profits.
so when the development of one of the coins decreased to drop much lower.