Scammers are always looking for different new ways to try and scam people, especially Telegram is full of them. When you join a group chat related to cryptocurrencies, you will most definitely get a couple of direct messages right after joining the group, others will approach with some patience so that you don't find it suspicious.
Yes you are absolutely right. Scammers continue to try to trick everyone by creating thousands of airdrops and often succeed. However, these scammers will not always ask you to add a wallet to their website to take advantage of them. There are many other methods by which they can easily cheat people. For example: Sometimes bots create airdrops and show many tokens or dollars. But there are some rules to withdraw them such as certain amount of dollars or certain amount of tokens will be required. After completing everything to withdraw they will give an address saying they need to pay network fee. Otherwise there will be no withdrawal. Even in this way, many people cheat.