According to this Indian government report, 110 million toilets and 2.23 million community toilets were built between 2014 and 2019 under the clean India drive begun in 2014. All states reported open defecation free in 2019.

Coverage estimates vary between 70-97% in 2019. I would assume the situation has continued to improve over the next 4 years so 15% seems like a believable figure.

https://www.pib.gov.in/PressReleasePage.aspx?PRID=1907510#:~....