Bitcoin has PoW, a limited supply, P2P transactions, is decentralized, has high security, it's the first and the front runner of cryptocurrencies.
As an established asset compared to other coins it doesn't need to be the most technically advanced, it has built up trust and has proven itself over the longest of time and such things can't be bestowed through sheer programming.
But the major fundamental aspect of Bitcoin is not something often spoken about and that is that Bitcoin is a medium of exchange chosen by genuine people. Unlike fiat currencies Bitcoin has not been enforced upon anyone. If you live in the US for example the IRS will expect you to pay taxes in USD which creates a real need for it's citizens to have that currency. Since the state controls the fiat money supply they then gain the ability to control peoples behavior. Through printing, distribution and taxation.
It is a perverse system where the properties of money is designed to serve the purposes of politicians and bureaucrats, not you. Inflation is good for the state, it lowers the value of state debts and thus makes them easier to repay, whereas it destroys savings for the prudent citizen. In fact citizens are incentivized to forget about their future and just spend everything they earn as soon as possible.
If the only reliable medium of exchange we had was fiat all our financial decisions would be manipulated by socialists trying to buy votes or to realize their wicked fantasies of controlling every detail of our lives.
Bitcoin was not made to serve anyone else but the holder and as such an entity it has been chosen to be a medium of exchange between millions of people. The biggest fundamental value of Bitcoin is that genuine people wants to use it out of their own free will. There is nothing that can compare to this.
