The sites that are seen as the best for aidrops are authentic for earning free tokens. Some are quite popular and they delivered as expected. They are Airdrop Alert, CoinMarketCap Airdrops, and Binance. A lot of people including me have benefited from them.
CoinMarketCap Airdrops works well for those interested in airdrops. With just a few clicks, they will tell you about the upcoming faucets and you can easily view which ones are still active. It's probably the safest way to find airdrops without wasting time on scams.
I'd add Telegram communities to the list, as many new projects are sharing their airdrops there, but I'm up for Binance and Airdrop Alert as the more trustworthy sources. The key is to always check if the project is legit before you join.