We are already in March 2021 now, I'm guessing first quarter of the year is almost over, now how many altcoins really benefits from btc hitting 50k ? In 2017 when btc hit 19k all altcoins are pumping like no tomorrow, even shitcoins made incredible bounces but why aren't we seeing such this time around?
That's because earlier the Bitcoin market was huge and the altcoin market was a mere shadow and smaller in size as compared to now. Today, the Bitcoin market is massive but also the altcoin market has grown with so many news tokens being made on the Ethereum and other blockchains along with so many coins coming into the market. The market cap is humongous now and hence one market doesn't influence the other too much.
It can be understood as mother (BTC) and son (ALTS). Earlier when the baby was inside the mother, if you feed the mother, the baby will also grow accordingly but now the baby has come out and grown himself so he doesn't need help from the mother for his growth, although doesn't mind it either. Now its growth is dependent on what he does of his own and isn't defined by his parents.