Having said that, I think the new laws are good for India. These are the arguments I have heard in favor of the new laws:
India introduced the current MSP related system back in 1960 to inspire farmers to grow those crops when India had a huge shortage of food grains, and was importing food directly from US (google 'ship to mouth india'). That is not the case now. India actually has a surplus of those grains.
Also, MSP covers only something like 15-26 food crops produced in India. For example, we all saw how onion prices dropped to insanely low prices last 2 years. There was no MSP for them. Just yesterday, there was news of a farmer in UP dumping 1000 kg cauliflower because of low prices.
Also, I believe this MSP cover is available only in certain states, which puts other states at a disadvantage. To make things complicated, there is a law that guarantees certain grains at low price for the poor. For example, the govt will give rice at 3 rupees to the poor. Govt has to buy the rice from the farmers because of the MSP system (say at Rs 20), and then in turn sell them to the poor at Rs.3 in a state which doesn't have MSP, thus putting the farmers in the non MSP states at a huge disadvantage.
Another reason I heard is that farmers are producing huge amounts of MSP crops such as rice and wheat because the price is guaranteed, while ignoring other crops that India has to heavily import (such as ground nut). The govt has to purchase the MSP grains no matter what, and the godowns have way more in stock than India could distribute (almost double or more last year).
Also, some of these MSP crops like rice require lot of water for cultivation, and considering the shortage of water in most places in India, govt wants to reduce the farming of such crops.