Don’t you think it’s easier, due to inattention when installing a compromised app, a privilege escalation attack through root or actually an invasion due to the amount of bloatware from companies that take their piece of the pie in the Stock ROM (even though they do would cleaning via ADB) and even worse rooted to block these suspicious traffic be something more harmful for the user?
Because the ability to steal the decryption password in RAM memory due to the unlocked bootloader is a little less likely for the thief to have.
I use LineageOS and I feel much better, since my cell phone is Xiaomi, than using MIUI, which is from a chinese big tech company and has proprietary code.