What's the point of automatic on-boot decrypting LUKS volumes?

Hello. You know that a "disadvantage" of wanting to have a LUKS volume decrypted at system startup is that a passphrase must be provided interactively. Since this is somewhat cumbersome, there are many methods that allow this passphrase to be indicated non-interactively using some type of keystore (systemd-cryptenroll, Tang/Clevis, etc). My question is: what is the point of having an encrypted disk, then, if it will be automatically decrypted when the system boots? A thief who steals my laptop with this automatic configuration would not have any impediments to accessing it! I'm missing some point here. Thank you so much