Thingking that way even you dont know bitcoin that much is not really understandable well people talk about this way because they tend to criticize evrything even they dont realy know much about something. Nothing could replace bitcoin because it has a headstart of a years to grow than new cryptocurrencies.
It never be happen that other digital currency supplanted bitcoin in light of the fact that bitcoin have high Security framework and high market esteem. Additionally bitcoin has high rising rate in the esteem. The notoriety of bitcoin is additionally a factor that no other cryptographic money can supplant bitcoin. The trust of individuals wherever on the planet on bitcoin is high is contrast with another cryptographic forms of money.
i think this will not happened that bitcoin will be replaced by other cryptocurrency until new currency came out and have higher price as well as popularity than people will leave to have interest in bitcoin and will follow that new currency.