People value gold. They just do. Gold does not have to do anything to have that value. It just has to exist. It's very difficult to destroy gold. You can buy it and leave it and it will not erode. No one needs to outlay money to keep gold valuable.
People value bitcoin (BTC) too. One crucial reason it is valued is because the bitcoin network, made up of miners, makes it very secure. It's very difficult to alter the ledger because you need to provide more computing power than all other miners combined.
The miners who secure the network make bitcoin very different from gold because the miners need to be paid. It's very expensive to run a mining operation.
Presently miners receive 12.5 bitcoin every ten minutes from the block subsidy. If we assume a bitcoin price of $10,000 USD then that means miners receive $18M per day to run the network.
All things being equal in about a year this will drop to $9M and four years later to $4.5M and then $2.25M and so on, as the amount of bitcoin created reduces.
Miners also receive transaction fees though these area lot less than the subsidies at present. These fees are variable. These fees are negligible compared to the $18M per day in subsidies.
If the price stays the same, all other things equal, then bitcoin (BTC) will eventually die.
Either transaction fees need to increase a lot or the price of bitcoin (BTC) needs to keep rising, in order to pay mines to secure the network.
This makes bitcoin very different to gold.
The best way (and probably the only way) for bitcoin to work is for it to become a huge system, widely used for all sorts of things, and have billions of transaction each providing a small fee.
There exists several different versions of bitcoin but I think the one that can grow to provide miners with lots a lots of transaction so it does not have to rely on the vanishing subsidy will be the one that wins.
Bitcoin needs to do this to compete with gold but if it does that it is so much more than gold, so different to gold, because it has so many more commercial uses, that it really should not be compared to gold at all.