bitcoin is techically more superior then ETH ,yes but the use cases are bigger for etheruem now!
real utility for ETH ARE BIGGER.
ETH: defi, icos, dapps, stable coins.
also the very good liquitity !!
BITCOIN ?
yes you can buy thigns with btc but so you can do with ETH.
but, you should remember without bitcoin, i don't think ethereum or other altcoins will born my friend
thats why market capitalizations of bitcoin will always higher than all altcoins.