It will not happen if the price of bitcoin still at the high price. Because only bitcoin that have really big price for each coin. To replace bitcoin, that crytocurrency need to be more good and have a new 'thing'
As long as many people are using bitcoin, I think theres a slim chance. It is the father of most altcoin they say and its true as many altcoins are fork from it. As long as bitcoin is used in many transaction, I beieve that it is here to say unless something happen and new programs or kind of blockchain is developed,funded,enhanced and promoted hardly to dislodge bitcoin.