India's 2021 Surrogacy Regulation Act already moved from a completely unregulated commercial surrogacy industry to an altruistic-only model specifically because researchers documented exploitation of lower-income surrogate mothers under the earlier unregulated system -- the policy shift itself suggests regulation, not a blanket ban, addressed the actual documented harm more precisely.
Feels like paying someone to carry a baby just seems like it could be exploitative of women who need the money, so maybe just banning it outright is simpler.