Dude, same with Montenegro real estate affecting the value of your apartment in Manhattan.
> If bitcoin was the only possible cryptocurrency but the hype around cryptocurrencies was the same, a bitcoin would cost substantially more today.
Just like if the rest of the land didn't exist, your Manhattan apartment would cost substantially more today.
If there was an exact replica of Manhattan (or if it was trivial to create it) - and I mean really exact with all the affordances it provides - think of an empty copy of the world, Manhattan is in the same place, but mostly empty (just established), that you can switch to with a keypress (and could switch back and forth) - what would happen?
Exactly. That's also the case for cryptocurrencies. You can instantly fork a cryptocurrency or a blockchain, but you're essentially copying a blueprint. You can copy Manhattan's city layout as a blueprint or other written/drawn representation, but you still need actual builders and resources to copy the physical structures, just like you need miners, mining rigs, and users to build an alternative to Bitcoin that has any value.
Assuming the same PoW algorithm, you'd need your alternative to exist for as many years as Bitcoin does to achieve the same blockchain length, for example, with a lot of distributed miners to achieve similar security guarantees.
You can create a Hacker News clone pretty quickly. (For the sake of argument, let's say you could do it in a day by forking an open source repo.) It doesn't mean your clone instantly devalues Hacker News.
Maybe if you grow your clone's community over years and it generates a lot of interesting discussions, people will use both, and maybe if eventually the discussions become more frequent and have higher signal:noise than HN's, HN activity may gradually decline as people decide to use your site more than HN. But this is about community and network effects, which you can't copy overnight. You have to build them over time.
Sure, you can move there toghether with a few 100 other people, but it won't be Manhatten as you know it.
The value is in the social network.
You can go and copy Facebook tech, it's not that crazy hard. Will you be Facebook? No because none of your friends are on FacebookGold.