Bitcoin increases, altcoin prices go up? I think you are wrong, when bitcoin prices go up,
altcoins tend to dump, and if bitcoin decreases then altcoins will also dump,
this is the relationship between bitcoin and altcoin, unless bitcoin is sideways then altcoins usually will try to go up.
Are you sure about that? Bitcoin has increased a lot this year, and looking at altcoins, they all increased as well. So what makes you think that when bitcoin goes up, altcoins go down? Because we do not have anything like that right now. Only coin that is down at the moment is XRP and that is because of whats going on with SEC, nothing more.
I agree that whenever bitcoin has a pump, for just a few hours (1-2 hours) alts look like they are dumping, but in reality bitcoin increases which means altcoins go down in bitcoin value, but as soon as they realize the price going up, they try to get back to bitcoin price, which makes them higher in dollar price. Look at the top 10 coins (omit the stable coins) and you will find that all of the coins listed there has increased in the past 1 year, which is the proof that when bitcoin pumps, altcoins pump as well.