Quoting him verbatim in this twitter thread. Will plug his pieces at the end.
Before starting, remember this: “varṇa is not a core aspect of Hinduism.”
We know for sure that “varṇa has nothing to do with race and ethnicity”. It might have been “a distinction based on occupation or based on the tribes that people belonged to.”
“In the Ṛgveda Saṃhitā, varṇa is not used in the sense of ‘caste’ or ‘class’.....”
“bright-coloured āryas are those who adhere to dharma while dark-coloured dāsas are those who don’t...”
“In Ṛgveda Saṃhitā, varṇa is only used in connection with two groups – the āryas and the dāsas.”
RVS 10.98.8 speaks of two brothers, Devāpi and Śantanu....younger Śantanu takes over the kingdom, Devāpi becomes a brāhmaṇa
“even in the period of the Vedas, during the later part of the Saṃhitā texts and with the advent of the Brāhmaṇa texts, the society became more structured. The distinctions of social class became more prominent....dāsa in later works came to mean ‘servant.’
Aitareya Brāhmaṇa 7.29.4 - śūdra is at beck and call of other three varṇa;he can be made to rise at will, can be beaten at will
Varṇa in the Purāṇas and the Smṛtis
Evolution of varṇa
Reformation of varṇa
Varṇa and Education
Idea in this thread was to simply introduce the origins of varṇa in Hinduism.