In the next few decades, this may be true. No altcoin or technology can threaten bitcoin's leadership position but in the more distant future it is difficult to say.
In all fairness, bitcoin is a product and result of technological development. Meanwhile, as we all see, technology is constantly evolving and even evolving extremely rapidly. So it's hard to know what will happen and we shouldn't be surprised if something outperforms bitcoin in the future. But like I said, that's not going to happen anytime soon, so there's no point in thinking about those things right now.
There are hundreds of thousands of alts circulating in the market but only handful of them are worthy for consideration and investment because most of them are shitcoins. Bitcoin competition is with these handful alts that are getting attraction from crypto community.
Bitcoin is leading the crypto market because it rolled out the idea of crypto currency and alts today are just trying to follow Bitcoin in some way. Can't say about the far future but for now bitcoin dominance is inevitable.