Some of them is because of there usage, demand etc. that have made them successful. Ethereum, Binance and Solana are a typical example.
Binance coin?
A centralized shitcoins that will go down when Binance goes and that was pumped with the fees Binance is fleecing its gullible users?
Nobody in its right mind would want to touch that unless forced by being tied with its finances to that exchange!
Governments and centralized authorities can create their own cryptocurrencies, but they face challenges in the areas of decentralization, trust and user adoption.
Why would they face such thing?
First they don't care about decentralization, trust is already there, you're using your national currency every day, you go to shop and that shop accepts it, that's the trust, as for adoption, that can come in a second, all they have to do is pay all govemermnt wages in that coin, then merchants will have no choice but to adopt it since they need to sell stuff, and that's it, it's done in a day.
If a govemermnt would truly want that they could simply stop printing cash, migrate all bank deposits and balances to the new CBDC and here you have it, how would you be able to stop it?