(A reminder:the Type-15 is more like a lighter medium tank rather than a 'light tank' which usually is an up-gunned APC)
Seems the Type-15 have been shown to the public in 2016& became operational since 2018 and obviously it's designed for mountain warfare; just which country is most likely to engage in mountain warfare with china? Obviously not the yanks nor the russians.
A Jan 9 2019 Popular Mechanics article: What You Need to Know About China's New Tank (popularmechanics.com)
"..Chinese army units working in rugged, mountainous border regions are getting some new firepower now that China's new next-generation light tank has gone into service.The Type 15 tank is smaller and lighter than the existing main battle tanks of the People's Liberation Army (PLA), meaning it can traverse terrain heavier tanks can’t cross..."
-----Seems hindu army didn't really take note or didn't bother until quite late when the Type-15 shown up at the border.
link(JUL 16 2021): Light Tanks: A Missing Priority for the Indian Army | ORF (orfonline.org)