Trust wallet is good but not completely reliable, it is only safe if your device is safe, once someone get access to your phone or laptop, your wallet can get hacked; it is a closed source hot wallet.
There are better wallets to be used than Trust wallet; Electrum wallet is very good for holding Bitcoin than Trust wallet since in trust wallet you can hold altcoin that are literally not completely safe because even the team can be strange at times; therefore, for easy access, use Electrum or Bluewallet to hold your bitcoin, but if you can afford offline wallets they are perfectly good because any wallet online is prompt to hack.
To some extent, trust wallet is in the bad, and I suppose even if someone will have access to your phone, you may create a passcode that would prohibit the person from having access to your trust wallet instead of your wallet being open without a passcode, as you mention. If your devices are safe, so are your assets, because some people are really reckless with their equipment. Because I have actually used trust wallet and have never had a security compromise. The only time I've encountered it was when I lost my seed phrase on it due to my negligence, and I no longer had access to my assets, and from that day forward, I realized the value of keeping your seed phrase safe. if it is bitcoin then electrum also a very good option to consider, I will agree with that since I’ve used both electrum and trust wallet, then for altcoin trust wallet is a good option to go with the great wallet that can be used. The most important thing is for your assets to be safe, because keeping your assets in your wallet is better than keeping it in an exchange, but you know how Lazy we can be and that is a very bad habit keep your assets in an exchange, which is not safe because exchanges can be attacked and so many reasons you should not keep your money their.