What is the authenticity of the "Black Banners" hadith, and does it apply to the current era?

The aforementioned Hadith (definition), narrated by Nu'aym ibn Hammad in "Kitab al-Fitan" from Ali ibn Abi Talib (may Allah be pleased with him), is very weak due to several defects: Abu Ruman is unknown, Ibn Lahi'ah became confused in his later life and was a mudallis (one who conceals defects in a Hadith chain), Nu'aym ibn Hammad has many objectionable narrations (manakir) and is considered untrustworthy by some imams, Al-Walid ibn Muslim practiced tadlis al-taswiyah (a specific type of Hadith concealment), and Rushdin ibn Sa'd is weak. These combined defects render the Hadith extremely weak, and therefore it is not permissible to engage with its meaning or apply it to current reality.