I agree with you that there are a lot of bitcoin competitors and may be able to replace bitcoin. But this is not easy to do, it is very difficult and has little chance of doing.
I believe the main enemy of bitcoin is not a crypto, but people who hate and dislike bitcoin.
The way people keep talking about competitions, they always make it sound like competition is actually that easy. Most of these coins are just busy promising and until they are tested on a very huge scale in terms of transaction before we can even know how sound they are and let's face it, most of them are just more like clones, except for those who have some product ideas that would drive in demand for the coin in the long run.
If people hate and dislike bitcoin, that is their cup of tea. Where were they when their mates were investing, believed in the long term and held? Moreover, if they hate bitcoin because of the transaction fee, I guess that is history now and I wonder why they did not hate Ether during the cryptokittens palaver.