Why were the killings of the Gibeonites in 2 Samuel 21:1 noticed more than that of the priests at Nob in 1 Samuel 22:18-19?

Question

1 Samuel 22:18-19 NIV

18 The king then ordered Doeg, “You turn and strike down the priests.” So Doeg the Edomite turned and struck them down. That day he killed eighty-five men who wore the linen ephod. 19 He also put to the sword Nob, the town of the priests, with its men and women, its children and infants, and its cattle, donkeys and sheep.

After the killing of the priests by Doeg the Edomite there is not much said about retribution and punishment for these killings

2 Samuel 21:1 NIV

During the reign of David, there was a famine for three successive years; so David sought the face of the Lord. The Lord said, “It is on account of Saul and his blood-stained house; it is because he put the Gibeonites to death.”*

But the killing of the Gibeonites is taken notice of to the extent that God punishes the land by causing a famine because of Saul's action.

What was special about the Gibeonites issue?

Answer 1

Joshua made a deal with the Gibeonites in 9:15 New International Version

Then Joshua made a treaty of peace with them to let them live, and the leaders of the assembly ratified it by oath.

But Saul broke that deal, 2 Samuel 21:

1b The Lord said, “It is on account of Saul and his blood-stained house; it is because he put the Gibeonites to death.”

As for Doeg's killing of the priests, Ellicott mentions:

And Doeg the Edomite . . . fell upon the priests, and slew on that day fourscore and five persons.—No doubt, assisted by his own attached servants, Doeg carried out this deed of unexampled barbarity. For this act the Edomite servant of Saul has been execrated in the most ancient Jewish writings perhaps above any other of the famous wicked men who meet us in the Holy Scriptures. For instance, we read in the Babylonian Talmud how “Doeg the Edomite, after his massacre of the priests, was encountered by three destructive demons.

One deprived him of his learning (concerning which see above, in Note on 1Samuel 22:9),
a second burned his soul, and
a third scattered his dust in the synagogues”—Treatise Sanhedrin, fol. 106, Colossians 2.

So according to the Babylonian Talmud, Doeg was severely punished