Some people might think that Bitcoin is the only useful coin out there, simply because of how its dominating over 50% of the market.
But I would say this is not fair because of 3 reasons:
1. Bitcoin is the worlds first cryptocurrencies and therefore, it has the first movers advantage.
2. All/most altcoins/cryptocurrencies are addressing different problems and use cases that Bitcoin doesnt aim to solve.
3. The crypto market is a decentralized free market where no one has autonomous power. Bitcoin could drastically fall in price in an instant.
Crypto-projects are evaluated by market sentiments and the use cases the project is intending to solve.
Im also not denying the existence of scams, and pump and dumps, and MLM coins, but the market will eventually filter these coins out.