if btc drops to 7-8k range what happens to alts?
According to my own experience if btc drops, the same happens to most of alts, only a few are not affected, the best time to trade alts is when btc is stabilized, also traders buy stable coins when btc drops. Currently it exists a project called mintMe where traders and investors can deal with entrepenuers by buying custom tokens that belongs to a particular project, this tokens can be created at the same mintMe platform.
That's because of money coming into the market. In order to buy alts, you pretty much need Bitcoin. Sure, there's exchanges with USD listings, but you're still going to trade for Bitcoin then trade the Bitcoin to get the alts. This is why when you see the Bitcoin market cap up higher, all the alts also seem to be going up in price as well.
The domino effects mostly being seen when bull rallied and pumped hard the market, bitcoin value lift up those quality alts and bring them to a good momentum. Same deal when bitcoin suffered, most investors are afraid to divert instead of buying alts, converting to stable coin is one of the option,
till the value bring good sign again it will move the market back, entire cycle will follow.