I read in the following article that indeed Joe Lubin has hinted on several occasions that there is a token in the works, but it really just hints only and no reliable source has confirmed the existence of a possible airdrop for Metamask beforehand, you should take the news from the official social media of Metamask and beware of Scammers, I believe that people who will Swap Tokens on MetaMask or use the MetaMask Bridge and some steps will be eligible to get Metamask airdrop in the future.

Source: https://cryptobriefing.com/metamask-could-launch-token-airdrop-heres-how-to-prepare/