Some people tried this before by branching off the bitcoin blockchain. That was called bitcoin cash, and it failed.
Bitcoins, meaning not any cryptocurrency but just actual bitcoins, are scarce and will almost certainly remain so.
At worst your coin takes time and attention away from Bitcoin, and thus takes value. At best it outgrows Bitcoin, and grows the entire space.
But that's like saying you could build your own alternative to Facebook by whipping up some corporate partnerships and venture capital. Go ahead, we'll see which one wins in the long run.
I think it would actually be easier to increase the supply of gold via asteroid mining than to increase the Bitcoin supply. That doesn't require consensus and will probably happen someday.
This is a cultural property of the community, not an intrinsic property of bitcoin. If Satoshi signed a PGP message with a compelling call to alter the scarcity it would likely happen; maybe you disagree, but the point is that it's very possible to change the scarcity because it's a distributed computer program.
Bitcoin is not just "a computer program", it is a program and a blockchain. The same program with a different blockchain is not Bitcoin (there are plenty of those out there). Adding more supply to the Bitcoin blockchain would require large numbers of people to work against their own interests, decimating the value of their own infrastructure investments and bitcoin holdings.
It would be much, much more difficult to change Bitcoin than e.g. the supply of dollars or euros which are considered scarce enough for most purposes by most of the world. And, I contend, even more difficult than changing the supply of gold via asteroid mining. I doubt that even the second coming of Satoshi would be enough to do it (and I also very much doubt that Satoshi is still alive, or that he would want to if he was, considering his known political/economic stances).
> It would be much, much more difficult to change than e.g. the supply of dollars or euros which are considered scarce enough by most of the world
This thread is about gold not fiat money, obviously the scarcity of fiat money can change, that's the whole point of fiat money.
This is simply not the case - see 2017 bitcoin cash fork or Segwit2X push. At the end of the day money is a human invention, meant to facilitate value exchange between humans. So it requires consensus between the users of the money, if some fraction want to change the rules they are free to.
We went for something we found in nature with properties that were pretty good for that, but with some downsides (not absolutely scarce, difficult to transport, easy to steal) to something created specifically for the purpose.
There still has to be consensus on using gold as money, if there isn't it will lose its monetary premium to something that has better monetary properties.
This is a great point. The choice to value gold as currency over other rare metals is 'a cultural property of the community' and yet not 'trivial' to change, just as Bitcoin's consensus isn't.
A single bitcoin is infinitely divisible, unlike most physical assets. How does that affect scarcity?
You're right that it is a community belief. If enough people were convinced that supply should be increased, they could fork the blockchain and move to the new chain. The change in supply would alter the price appropriately.
But that's no different to the community belief that it has any value to begin with. If everybody was convinced that gold was worthless (outside of its practical industrial uses), it would cease to be a store of value too.