I think he is confusing Atomic with Binance, but Trust Wallet is just as closed source, so, ironically there is no point in trusting such wallets. You might as well store your coins on Binance. They might have a lesser chance of being hacked. Although looking at the past history of crypto exchanges, they eventually screw up, get hacked or straight up steal your money.

I agree that any wallet which is not 100% open source is a red flag. Otherwise behind the code could be a third party, trying to take your money with a strategically planned hack.