the reason that price of Onion going down fast is not the dev selling it, just because a lot of people who already got airdrop coin in previous rounds but they are blacklisted this week, so they just break up the rule that can't sell more than 10%. But these selling is nothing, there are more and more people participating the Onion, and the price will go up soon and very fast and refresh the record time by time.
That would be such a threatening situation on most of the holders right now,and when supply was more I think it's not a good way to hold it due to less demand on buys. Air drops is just a free coins to collect and be traded quickly like selling it directly to the marketplace, worst case now is nobody is getting interested with deeponion due to it's market cap isn't that progressive. If I were that airdrop coins holders, its better to dump those coins immediately after it's listed on the exchanger because more airdrop collectors were really selling their collected amounts, that's why price is getting lower. It's like a saying that "stike while while the iron is hot" same as what's happening now, if you see the coins is dying; well you can sell it immediately in order to save it and take your break even profit.