Why despite the implementation of Green Revolution, 65% of our population continued to : be engaged in the agriculture sector till 1990?

Although the advent of Green Revolution, Indian agricultural production increased substantially that enabled India to attain the status of self-sufficiency in food grains. This increase is substantial only in comparison to foodgrain production in the past. India failed to achieve structural transformation associated with the economic growth and development.
The industrial service sector in India failed to generate significant employment opportunities in order to attract and absorb excess agriculture labour. In India, between 1950 and 1990, the proportion of GDP contributed by agriculture declined significantly.
This makes it evident that the industrial and service sector growth was not very significant and thus, could not provide employment opportunities to the surplus labour from agricultural sector leading to disguised unemployment in agriculture. The slow growth of secondary and tertiary’sector has been responsible for majority of population (approx 65%) remaining in agricultural occupation till 1990