You're not completely accurate, Manusmriti may have been just one such religious texts but its the one that stuck around. And it has found its roots even among today's Hindus. Only a blind man would claim that we do not suffer from caste-ism even today. Any corrupt cretin like mayawati or lalu can become the CM based on the caste card (playing on lower castes and higher castes both), ranvir sena operates like a quasi taliban force killing lower caste people, brahmins go and molest dalit women in UP, the naxals find a ready source to exploit in the caste enforced hardships faced by many in the tribal areas. See, a member pointed out earlier that a religion cannot be judged by what it says or what it preaches..the more important criteria of judgment is how it is practiced and while in many cases Hindus are relatively better at following their religion peacefully- we still have groups like Abhinav Bharat which feel the need to pick up arms in some misguided attempt at "safeguarding Hinduism".
Bang Alore sir is correct in stating that NO religion is secular. The meaning of secular is as follows: Denoting attitudes, activities, or other things that have no religious or spiritual basis, AND NOT our commonly held idea that to be secular means to be respectful towards all religion or to follow a strategy of appeasement. By that, correct, definition of secularism NO religion can ever be secular and thus neither is Hinduism.