The value of anything as a medium of exchange and store of value always depends entirely on whether or not a critical mass of people want to use it as such. Once you establish that a thing satisfies all the properties of money, or close enough, then the only question is network effect. Even if minor theoretical improvements could be made, it has to be 10-100x better to overcome runaway network effect.
Sea shells and bags of salt were drastically better money than mentally keeping track of favors owed in a small tribe, because we could expand our exchange of favors beyond dunbar's number to cooperate with people we don't intimately know. Gold was much better than sea shells and salt because it's globally scarce and durable. Paper backed by gold was much better than raw gold, namely because it is drastically easier to trade, transport, and fractionalized.
The technical nature of bitcoin isn't special and it can be trivially forked, modified, and a new network started for near zero cost. That's exactly what coins like litecoin and dogecoin did. Copy paste bitcoin code, change the name and some constants, and boom, new money. What makes bitcoin special, and why there can only be one dominant cryptocurrency long term, is network effect. I don't care about litecoin and dogecoin, because barely anyone uses them relative bitcoin. Barely anyone is developing and building on them as a foundational layer. The only reason anyone cares about dogecoin these days is because one eccentric billionaire has a hard on for it, and that's way too small of a bus number to store a significant amount of my wealth in.
The same holds true for any network protocol. I can copy paste libraries for TCP and make modifications that I think will make it far superior to the current form and release it to the world! And nobody except hobbyists will use it because standard TCP has an unassailable network effect. You have to have an extraordinarily compelling reason to change, and even then it will take decades (see IPv4 to v6 transition for example).
The thing about bitcoin, is that it is the first truly digital money. Fiat currencies like the USD have been trying for decades to pretend to be digital, and they'll probably try harder to use blockchains to make it better, but ultimately it's still fundamentally stuck with an analog foundation defended by guns and tight cliques of trusted human gangs, which makes it globally weak relative to bitcoin. That's why bitcoin has a 10-100x advantage over dollars long term. It's natively digital, open, and permissionless from day one.