Yo, come on its not that monolithic of an opinion. Not everybody opposes it, some vigorously support it. The primary problem we have in Trump's own words is "Jobs,Jobs,Jobs". Frankly there aren't many. Past govt. in Centre have a long record of totally ignoring our needs. We don't have much industry, nor do we have much tourism, our state govt. are always low on cash. But despite all that people have aspirations, what to do ? can't be helped.
Now some of the states seem to be getting on their feet economically, including the one I come from. We still have a long way to go. In this backdrop we have an influx of illegal immigrants. That naturally causes a competition of resources, taking in people of a certain religion while blocking some other won't fix the competition of resources. It won't help us anyway. That's where the opposition to CAB comes from.
There is another view point to this which is basically the one most of us here share, demographic change that eventually fuels secession tendencies. Those who understand it are likely the ones with more exposure to the wider world, not every body has that, I am afraid. Then there are the son of a b***h politicians who will play on these subjects to win votes. This is what you mostly see on TV.
What the local BJP people are doing is promising a constant support from the Centre : financial, technical or otherwise to us as a way of weakening the opposition to CAB and allaying local fears. But people are unlike to be rejoicing over it. I remember, as recently as the late 90s-early 2000s, we asked the Central govt. for funding to build a railway line(we didn't have railway connection then), they pretty much told us "go f**k yourself" diplomatically. Just my two cents.