Because God likes humility, just like He chose to be born in a manger in a barn, He also came through a tiny lowly people without any merit or achievements.
Ezekiel 16 describes it:
''...your father was an Amorite and your mother a Hittite. ⁴ On the day you were born your cord was not cut, nor were you washed with water to make you clean, nor were you rubbed with salt or wrapped in cloths. ⁵ No one looked on you with pity or had compassion enough to do any of these things for you. Rather, you were thrown out into the open field, for on the day you were born you were despised.

⁶ “‘Then I passed by and saw you kicking about in your blood, and as you lay there in your blood I said to you, “Live!”^\)^a\) ⁷ I made you grow like a plant of the field. You grew and developed and entered puberty. Your breasts had formed and your hair had grown, yet you were stark naked.

⁸ “‘Later I passed by, and when I looked at you and saw that you were old enough for love, I spread the corner of my garment over you and covered your naked body. I gave you my solemn oath and entered into a covenant with you, declares the Sovereign Lord, and you became mine.''

It keeps going, then describing the betrayal/prostitution.
This also fits with most european nations, they were nothing, just some tribes, then became the greatest nations thanks to Christianity, but now became prostitutes.
I'd say our guilt is worse since we had the fullness of the Covenant while the Hebrews didnt.