altcoins follow the bitcoin in the bull marker if btc goes up then alts will show the positive movement as well. but this may there is big crypto event ahead which is bitcoin halving and i think that people will gather more btc by dumping their alts
They follow each other in both bull and bear. The difference is that in bull altcoins tend to lag behind bitcoin and in bear market they get closerto it or even percede it with dumps. Also in bear market altcoins become more volatile and take bigger hits and in bull they pump more percentage-wise.
I don't think this time something will be different.