Polygamy was already being practised in Arabia before Islam. Surah 4 verse 3 restricts and regulates how many women man can marry in Islam.
Many people forget the the last part of this verse, where it tells men that if they fear they won’t deal justly with their wives to just marry one.
Further on in surah 4 verse 129 it says that men will never be able to be equal with their wives even if they try to be.
If the intent for fairness is not met then Islam prohibits polygamy entirely.