The summary verse for this contention might be:

“Let peoples serve you,
Nations bow down to you.
Be lord over your brothers,
Let your mother’s sons bow down to you.
Cursed be everyone who curses you,
Blessed be everyone who blesses you.”
Gen 27:29

It does matter what the nations do, morally and ethically.

“Righteousness exalts a nation,
But sin is a disgrace to ANY people.”
Prov 14:34

Righteousness does raise up, exalt, peoples, nations. These things do come into account. Jesus in one place speaks of doing trivial deeds that are good.

“Whoever gives one of these little ones just a cup of cold water to drink in the name of a disciple, most assuredly I tell you he will in no way lose his reward.”
Mtt 10:42

This, and the KJV of this, is really paraphrase of the verse, which is a strong negative of that person having a chance of losing their reward. I don’t think it means that everyone that gives a cup of cold water to someone in need will go to heaven. He is saying that even little things count, and will bring their proper reward. God sees and knows and will bring us to account or rewards for even trivial things.

“I tell you that every idle word that men speak, they will give account of it in the day of judgment.”
Mtt 12:36

A scary thought to most of us. However it not just the bad things, but also the good things that are remembered and accounted for. As the Hebrews in Jerusalem were told,

“For God is not unrighteous, so as to forget your work and the labor of love which you showed toward his name, in that you served the saints, and still do serve them.”
Heb 6:10

Counting one thing as another!

Of course good works are NOT enough to deliver us from the penalty for our wrongs, but all is taken into account. Unfortunately, not all of us have the same advantage in being properly instructed. Circumcision was the sign of the covenant in the Old Testament. Even so,

“If therefore the uncircumcised keep the ordinances of the law, won’t his uncircumcision be accounted as circumcision?”
Rom 2:26

It does not have to be every single person in a nation.

Sometimes it can be just one or two. The righteousness of one good man, Joseph, brought blessings on an entire plantation.

“It happened from the time that he made him overseer in his house, and over all that he had, that Yahweh blessed the Egyptian’s house for Joseph’s sake; and the blessing of Yahweh was on all that he had, in the house and in the field.”
Gen 39:5

When Abraham pleaded for wicked Sodom and Gomorrah, he asked God, suppose that ten righteous men are found in Sodom and Gommorah?

“… And He said, “I will not destroy it for the ten’s sake.” ”
Gen 18:32

Still, the conduct of the nations counts

“… Cursed be everyone who curses you,
Blessed be everyone who blesses you.”
Gen 27:29

So it will be!

Scriptures are from the World English Bible (WEB), a copyright free revision of the original ASV American Standard Version 1901