To waste your money and time....

Hmm, shitcoins? Never heard about it. I've heard about Bitcoin, Solana (SOL), Filecoin (FIL), Polkadot (DOT) and other.

If we omit the "strange" name of the coin you've mentioned, I'll try to reply your question. First, there's a good article on Web3 and how it works. Second, many of the Web3 protocols rely on cryptocurrencies. They offer a monetary incentive (tokens) to anyone who wishes to help create, govern, contribute to or improve one of the projects. So, yes, we really need coins in Web3.