[sure why not]

Just saw this in my feed.

All I can say is YAY! It's about time

[experimancer]

How does the unlocked bootloader benefit us users?

How does it help developers, what can be enabled and configured in Nokia 6 phones when the bootloader has been opened?

[sure why not]

With these Nokia phones running close to pure Android, and no manufacturer/carrier bloatware, there is not a huge need for root.

I would still like to be able to run Titanium Backup and a few other applications that require access.

Developers probably don't see much reason to work on a low-mid range device that has small market share and is not heavily skinned.
Some people used to their legacy rom might choose this phone if they could install it.