No altcoin is build on Bitcoin network till now. And I hope in future also there will be none. This is the fun fact of bitcoin.
There is no person or foundation who can control it or create it or destroy it. Fully anonymous. This feature attracts people to invest in bitcoin more than other coin as no one will be comfortable to put their funds into others custody. That's why big investors are in bitcoin and Bitcoin has the major Marketcap in Crypto.
Here is the noticeable thing, emotion rather sentiment play a huge role here. As bitcoin goes down it makes the market sentiment bearish. People starts taking out their money. That's why the altcoins also goes down. Here we can't apply the basic calculation logic.