The problem is you don’t know who “the righteous of all the nations are..
have a share in the world to come.”
Romans 3:10
As it is written: “There is no one righteous, not even one;
Psalm 14:1 For the director of music. Of David. The fool says in his heart, “There is no God.” They are corrupt, their deeds are vile; there is no one who does good.
Psalm 53:1 For the director of music. According to mahalath. A maskil of David. The fool says in his heart, “There is no God.” They are corrupt, and their ways are vile; there is no one who does good.
Psalm 143:2 Do not bring your servant into judgment, for no one living is righteous before you.
Deuteronomy 30:11 For this commandment which I command thee this day, it is not too hard for thee, neither is it far off.
12 It is not in heaven, that thou shouldest say: ‘Who shall go up for us to heaven, and bring it unto us, and make us to hear it, that we may do it?’
13 Neither is it beyond the sea, that thou shouldest say: ‘Who shall go over the sea for us, and bring it unto us, and make us to hear it, that we may do it?’14 But the word is very nigh unto thee, in thy mouth, and in thy heart, that thou mayest do it.
Deuteronomy 17:8 If there arise a matter too hard for thee in judgment, between blood and blood, between plea and plea, and between stroke and stroke, even matters of controversy within thy gates; then shalt thou arise, and get thee up unto the place which the LORD thy God shall choose.
9 And thou shall come unto the priests the Levites, and unto the judge that shall be in those days; and thou shalt inquire; and they shall declare unto thee the sentence of judgment.
10 And thou shalt do according to the tenor of the sentence, which they shall declare unto thee from that place which the LORD shall choose; and thou shalt observe to do according to all that they shall teach thee.
11 According to the law which they shall teach thee, and according to the judgment which they shall tell thee, thou shalt do; thou shalt not turn aside from the sentence which they shall declare unto thee, to the right hand, nor to the left.
12 And the man that doeth presumptuously, in not hearkening unto the priest that standeth to minister there before the LORD thy God, or unto the judge, even that man shall die; and thou shalt exterminate the evil from Israel.
By the way, in Jewish belief, there are perfectly righteous in every generation (tzadikim.) They do not sin in though, speech, or action. Their every waking (and even sleeping by tradition) moment is deeply attached to G-d and what He wants them to do in His world (Torah study and performance of mitzvos.) These men and women are not mythical—they are not super-human. They are godly (not G-d) humans. And our charge as Jews is to try to think, speak, and act like them.
We fail a lot but, G-d likes a struggle.
But righteous do exist. (in opposition to your quote from Romans)
Re “world to come,” those non-Jews who keep the seven commandments have a portion in the world to come. Take a look at the information and take a look at a perfectly righteous man (lower right of the page.) It’s good just to see the face of one to make it a tangible experience.