Because no-till doesn't scale. It's incredible for market gardening to feed the rich who can pay a premium at a farmers market, but it's not going to feed the world.
No-till feeds the world. The amount of no-till in current full-scale agriculture is by far the biggest proportion in North America and Europe.
Modern farming already uses low or no till.
The estimated area of no-till in Brazil is between 33 to 50 million hectares. It won't be hard for you to find videos of no-till corn being planted following soybean. There is also grass cover that is planted after the main crop season, that is later grazed. This cover stays till the next year and the new crop is planted without tilling. You may need to use "plantio direto" "milho safrinha" and "braquiária de cobertura" plus some translation.