In Islam, oppression and wrongdoing will not go be overlooked. God talked about oppression very clearly in the Quran, which is the last revelation, and the literal word of god. In Chapter 21: Verse 47
He says:"We will set up the scales of justice for the Day of Resurrection, so that no soul will suffer the least injustice. And even if it's the weight of a mustard-seed, We will bring it up."
On judgment day Allah will gather the first of mankind from thousand of years that passed, with people who are yet to be born and set foot on this earth. Every single soul will be called on that day, and will be questioned on how they and Allah will serve Justice to everyone. Anyone who was ever oppresed or wronged throughout their life time get to decide on whether they want to punish or forgive the opressor, in a fair and just way.
Allah does not forget, But he does give a chance for humans to repent and seek forgiveness. Allah says in the Quran [Chapter 14: Verse 42] "Do not ever think that God is unaware of what the wrongdoers do. He only defers them until a Day when the sights stare. (Judgment day)"
Also from what passed on to us from prophet Mohammad:
Sahih Muslim 2578: Allah's Messenger (ﷺ) said:"Be on your guard against committing oppression, for oppression is a darkness on the Day of Resurrection, and be on your guard against stinginess for stinginess destroyed those who were before you, as it incited them to shed blood and make lawful what was unlawful for them."
Sahih Muslim 2581: Allah's Messenger (ﷺ) said:"Do you know who is poor?| The companions said: A poor man amongst us is one who has neither dirham with him nor wealth. The Holy Prophet said: "The poor of my people would be he who would come on the Day of Resurrection with prayers and fasting and Charities but (he would find himself bankrupt on that day as he would have exhausted his funds of virtues) since he hurled abuses upon others, brought calumny against others and unlawfully consumed the wealth of others and shed the blood of others and beat others, and his virtues would be credited to the account of who suffered at his hand. And if his good deeds fall short to clear the account, then his sins would be entered in his account and he would be thrown in the Hell-Fire."