...When you finally import the wallet you'll be asked for add some gas fee and as soon as you add Tron to the wallet it will be moved automatically to another wallet. ..
I don't think that this kind of fraud can cause even minimal financial damage. If a similar situation happened to you, how much would you deposit TRX for the commission? I am sure that no one would have transferred more than a few cents, since this amount would have been enough to withdraw coins from the wallet.
It is not many people that will fall for this type of scam. It can only be some naive people or people who do not know much about cryptocurrency.
It all depends on how much was displayed in the wallet. If the scammers decided to display 50,000 dollars worth of coins, it will not be difficult for anyone to pay $100 as a fee to withdraw fifty thousand dollars worth of coin.
If not for greed, no one is supposed to fall for this type of scam. It is just a clear example of reaping where you did not sow.
It is not that you mistakenly discovered where someone hid their seed phrase. In this case it was sent to you outrightly in your inbox, which shows that the sender has some hidden intention.
The best thing is to delete the message and disregard it totally. But then anyone who falls for this type of scam does not deserve my sympathy.