Realme (OPPO's increasingly popular sub-brand) has decided to release a tool enabling owners of its 2 Pro device to unlock their bootloaders. However, it involves rather more steps than the average adb-command process for many Android phones. Realme also claims that bootloader-unlocking in this case increases the risks to user personal data and security.
https://www.notebookcheck.net/Realme-2-Pro-users-can-now-unlock-their-bootloaders-but-there-are-caveats.394916.0.html