if BTC goes to 100k almost all the altcoins will go up too in USD price, and many of them will be squeezed and value less against BTC
what happens after that, no one knows but can be the same effect as in 2017
Of course, Altcoin will follow the price of Bitcoin, we can see the experience in 2017 where when the price of Bitcoin increased dramatically, the price of Altcoin also went up. But I don't think the price of 100k can happen in the near future, because it requires 12x the current price.
It would take a lot of market cap to hit the value of $100,000 and i think it might happen but it would take a lot of years to happen. And it will also depend on the investors if they will still bought even thou the price is really that high.
And as of now, there is a possibility that the value of BTC could reach more than the ATH and hopefully it will go much higher and no more DUMPS to happen but that's the flow of the market, we cannot stop it.