I'm thinking that if someone ever released a coin with a lightning network, all the other coins will just copy the same thing and the competition will be gone once again. Bitcoin will still prevail if that happens.
Their are so many altcoins whose network has lightning speed but even then they are not success, the main reason of the success of bitcoin is it is not controlled by any one but altcoin are controlled by the developer and when ever they want they can change or do anything to coin. This is the main reason of the altcoin not getting success