Wa Alaykum Assalam and thank you for your question.

Initially, this hadith is daif (weak), which means that it is not authentic and we may not rely on it; this is the purpose of hadith classification, which is to tell us the level of authenticity of hadith.

This whole subject is no longer applicable in our time because there is no more slavery. Islam came to eliminate this social ailment and it did succeed over time; it was a gradual process.

Therefore, any questions regarding slavery are not only inapplicable but will not be well understood by people who have never lived at the time of the Prophet (peace be upon him).

I hope this helps answer your question.

Salam and please keep in touch.