Eth replacing bitcoin is ridiculous and even thinking Ripple to do that is much more. Last year, bitcoin was also stuck in it's price for so long and it was just $1k so seeing bitcoin not moving today is just normal and does not mean anything like it's finally resting for good.
There is no way any other coin replacing bitcoin and sure the price of bitcoin is looking strong even though the market went down today, but if you compare the entire market the price of bitcoin did not come down like the rest of the coins. We might hear negative news from the market which could impact the price for the short term but looking forward it is a positive market.