This looks highly suspicious and they are trying to get active key or password. Once they have that they will take whatever they can from your account. A similar scam is going on in Hive. Word has it there is no airdrop. This user's account is hacked. They need to change their password.

On steem-engine.org they have a warning: "ATTENTION: Please do NOT click on any links that promise you can claim a free airdrop!
Most of those links are created by scammers who want to steal your account keys."

In the event of a true air drop on the Tron network they already have your user name and that is all that is needed for an airdrop.