Well that's what they said like in 2018, after the Bitcoin's bull run, there were several attempts to topple if from the top, like by ETH and Ripple. And yet Bitcoin stood those challenges. While those two altcoins remain dominant in their own way, however, there are some altcoins that challenge them as well and it seems that ETH might have lost some of it ground already. As compare to Bitcoin wherein it remain and have dominated as high as 60% during it's height. So the answer might be very obvious by now, that no one can take over the market. And again, if we look at altcoin market right now, it seems that it is saturated and every use case that you might think of have been developed and yet it's not even get close to what Bitcoin did cornering the crypto market and it might continue till the next ten years.