Specifically for extracting natural gas. Gas is now much cheaper than coal which is one of the reasons coal fired power stations and coal mines are closing. Gas has a smaller percentage of carbon than Coal so creates more steam, less C02 for the same heat.
Fracked gas has replaced conventional oil in the US as the default heating fuel. This is the reason why America's carbon output is falling faster than anywhere else on Earth.
Yes, but it's still highly likely that making a huge source of carbon energy in the ground economically viable will be a big net negative for climate change in the future; I think the likeliest outcome is you've just delayed the use of those other more polluting resources by some number of years.
Now, the delay could be a net good thing if it gives non-polluting sources like solar, wind and nuclear more time to become cost competitive, but at the end of the day fracking has enabled billions and billions of barrels of oil to end up as CO2 in the air where previously it would have been left in the ground.
It makes buying solar panels cheaper, installing them cheaper, and the required batteries cheaper because the trucks that mine silicon use diesel and the people working at the dollar panel factory get there by petrol.