working as intended (tm)

... but i am a special robot, one of the verry few Necron-Lords! It's not like we have a Necron Lord for each battle we fight

... for a short ammount of time...

... as i am dead even by necron standarts after that...

... yes it does sadly. Or we would have C'tan showing up in every friggin engagement the Necrons fight

It's okay.

After eating that star, all the nearby organic life will die too. : D

Well... have it your way, im done here with trying to explain

Why would robots not be okay with snackrificing one robot to eat a star and kill all life in the system by removing the star as a source of heat and energy and gravity?

Aren't Necron Lords the only Necrons to retain most of their personality while the rest are drones?

Does it matter?

Just copy their personality files and make more robot-leader-lords.

And make more robots.

They have factories that make robots.

And if they don't, they have robots that can make factories that make robots.

According to the lexicanum they recapped that fact. It was indeed like this, that the common Necron lost his personality while only the Lord himself had emotions left (even if they wern't many...)
But apperantly, now also the normal Necron has shadows of his personality left

How does the shadow of a personality differ from the personality itself?

Diluted, blunted, and arguably no longer a continuation of the original incarnation.