Correct. Like others have said before me, the Trezor itself doesn't hold any bitcoin/crypto. Look at Trezor as a Key to open your house where you have all your belongings... you will only be able to access the funds associated with your Trezor if you use it to unlock the access to them. Even if you loose the device, provided that you still have your seed phrases, you can re-gain access to your funds by simply restoring the wallet.dat file in Electrum, for example.

The benefit of Trezor is that the keys are generated in a total different device other than your PC, to increase safety. You can also even add a password to your Trezor (if you end up buying the Model T) that even if you loose the device, nobody can access the interface because it's password protected.

Trezor also implements the so called passphrase, which further increases the safety of your funds. You can learn more about it here - Passphrase on Trezor

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If someone can find that piece of paper they can indeed access to your coins, so you better keep that paper in a high secured place...