I would acknowledge that opportunities were denied based on caste, But 'Denied education for 2700+ years' is a strong claim with out any proof is taking your argument little too far.
Aatukuri Molla was a celebrated poet, not from upper caste.
She faced initial resistance not because of her caste, but because of her choice not to use sanskrit while translating the epic ramayana to Telugu.
Once she proved her talent, she was granted audience to emperor and awarded with title 'Gem of Poets'.
Her version of ramayana is still popular to this day.
Annamacharya, is also another poet who being a brahmin, also faced similar resistance from established scholars because he composed his poems with local lingo rather than sanskrit.
TL;DR
Casteism is an Organized mafia in India since 700 BC https://archive.is/PdiUF
BC/SC/ST people, 80% in India, were denied education/employment and basic human rights for 2700+ years as per https://en.wikipedia.org/wiki/Rigveda in https://en.wikipedia.org/wiki/Timeline_of_Indian_history
In 1932 https://en.wikipedia.org/wiki/B._R._Ambedkar, Architect of the Constitution of India demanded a separate country (not Reservations/Affirmative Action) for them https://en.wikipedia.org/wiki/Communal_Award
https://en.wikipedia.org/wiki/Mahatma_Gandhi opposed it, bullied and bribed them with https://en.wikipedia.org/wiki/Poona_Pact