In my opinion why can altcoin not replace bitcoin and what makes Bitcoin different?
There are so many altcoins and they are starting to eat into the Bitcoin market! First, market capitalization is a highly manipulated metric. Second, the market naturally has a lot of noise and only smoothes out over long periods of time.

Due to network effects and decentralization, Bitcoin is different from all who pretend to be the throne. That does not mean that there is no way to replace Bitcoin. Such statements will be too broad and optimistic about Bitcoin opportunities.

But what is clear from studying the history of the cryptocurrency market is that Bitcoin has prospects that will not be easily released. New "features" at the expense of network effects and decentralization are not a very good exchange.

What does it take to replace Bitcoin?

Most likely an innovation is at least as big as Bitcoin itself or a bug that makes Bitcoin insecure. Tweaking some variables will not be enough for other coins to catch up. Even adding large features (eg privacy) might not be enough because network effects have created a special ecosystem for Bitcoin.

Decentralization is also not easy to achieve, and altcoin has not found a way to point their coins in that direction. Even the idea of ​​guiding coins in the direction of suggesting coins is centered! It is hard to imagine a maker of valuable coins who want to decentralize because they are given emotional, economic and social incentives to maintain power over their creations.

Bitcoin is different because unlike altcoin, Bitcoin creates a new category and has network effects as a result. Bitcoin will continue to be different because it is not like a centralized coin, it is market driven, does not change and cannot be changed. This is a property of large value storage and this gives Bitcoin a utility that other tokens do not have.