I was under the impression that Bitcoin has remained dominant because most other coins are affected by the underlying price of BTC. Anything crypto I see most

I was under the impression that Bitcoin has remained dominant because most other coins are affected by the underlying price of BTC. Anything crypto I see most regular people doing is basically... USD -> USDT (Tether), and then USDT -> USD I guess that bypasses BTC, but has a heavy focus on fiat. Are we still in the days where... if BTC goes down, ETH goes down?