I don't know about the ancient Arab world but Roman slavery wasn't race based, wasn't generational, slaves could buy their freedom, and eventually slaves gained some forms of legal protection. Oh and it was almost 2000 years ago.

Same in the Arab world/Middle East.

Slaves in the Arab/Ottoman world could purchase their freedom, were not enslaved by race (rather as POWs), their children were free, had some legal protection, and had the potential for upward mobility (in rare cases slaves that became viziers, ministers, or kings). Also Arab society post-Islam highly encouraged freeing slaves (considered a major virtue/source of reward/form of penance).

May be more accurate to say slavery in the US was less brutal than slavery in the French Caribbean or Spanish Argentina.

> I would argue slavery in the US was far less brutal than that of the ancient Arab world and Rome

And your evidence to support that is..?

There were essentially no limits to the brutality that could be inflected on a slave in the US, so any brutality that you find in the ancient world is easily matched by a brutality inflected in the US.