It's a very good question, I think you are right that the people use bitcoin for most of altcoin dealings. Hence the price is dependent on it. Some other coins like ripple and Etherium have also created there place in the market as there projects are quite good and they are reliable. But according to me I think bitcoin is most reliable.
I must say that you are very clear with your concepts and you are really inspiring and motivating people who are thinking to invest in crypto. I admire and appreciate your work @louisthomas keep it up and I will be waiting for your next post good luck my friend