If you want to farm reasonable airdrops I suggest that you stick to testnets, they might take time but your efforts won't be wasted.
I simply don't understand this part of your post. Why should someone farm testnet if he isn't a developer or something? Testnet is just a separate Blockchain for testing a new project. Or is there any other meaning to it I don't know of? Those telegram airdrops were fun while it lasted. A lot of persons made some really good amount of money just by taping or playing those games. There are still a couple of them but there aren't worth wasting your time on. Like you said, the best way to making money in crypto is by trading and holding. So I agree with that.
Testnet airdrops is live and it is not only for developers; people like me and you can test the project and get paid for it when they lunch during TGE.
In fact, these testnet are far better than all these telegram minings that wasted many people’s time and effort; and while we and other people were mining through tapping, some people were running nodes and participating in testnet sad they earn thousands of dollars.
Telegram airdrops have spent their time and I think the hype is no more, but testnets has been there for long and many projects are still coming up.