It discusses that in the article. 80% Of Indians are Hindus and believe cows are sacred. Suggesting they abandon their cultural beliefs just to maximize yields is ignorant of their way of life. Not everyone needs to live or believe like us.
Cows in Indian cities today live in slums, surrounded by pollution and disease. They feed on roadside garbage, and their stomachs become compacted with plastic bags.
This is the second top result from Google detailing more of the suffering: https://sharan-india.org/cattle-in-india/
Proper slaughter would improve the conditions of cattle.
And if everyone around me had to adjust to a culture where dogs were treated like the dairy and veal and cattle industry? There would be an outcry.
Even that has some internal inconsistency. The cows are too sacred to kill, but not sacred enough to vaccinate against a preventable disease? The article says that vaccination might drop milk output by 20%, so it seems like to them cows are less sacred than the almighty dollar (or rupee).
It's not as if everyone is just doing fine and some rando person demanded they 'maximize yields' the problems of these cows being sick impacts the folks who own these cows too...