stocks has been having a very terrible time for some time now while bitcoin is still above $10k and stays strong. not to mention that there has never been any correlation between the two and it has not started either, even though some newbies always panic for no reason with any noise!

as for altcoins, they are traded mostly against bitcoin itself. there is no "fuel" to come out of there and go into bitcoin. the reason they get dumped is that day-traders who were profiting from altcoin pumps while bitcoin was stable pull their bitcoins out of them to come back and sell bitcoin for fiat and day-trade bitcoin on its ups and downs while it is rising. similar thing happens when bitcoin price drops that is why altcoins dump on both bitcoin rises and falls.