I think it's fair to say it's not a scam, but only if you received the airdrop for free. I would caution anyone that spends their own money to invest in such early and high risk project. It's your own money, make your own decisions.
So let me repeat, there is probably no real evidence DeepOnion is a scam, only theories/concerns. But there are some issues that would make me a little concerned if I'm spending my own money to buy, specifically:
* no activity in the
official github, last commit over a month ago
* no new release of client update, so I'm not really sure if there is any development activity going on
If the developer could publicly show actual development activity by showing new commits in github or release new client updates, that would be ideal. I'd be then comfortable with spending my own money to buy in this project.