I think that any airdrop that asks for "gas fee" or "donation to get double airdrop" is a scam..
Not really but I would avoid them anyway. Also the best way is to search in google about such project, sometimes scammers just use same name of project to get your data (probably later for spam). That's why it's the best to use your new email just in case if you don't wanna get mass spam in the future or maybe even phishing mails.