Some people want to ban Bitcoin mining because it uses much energy, increasing the safety of the system to levels no other blockchain has.
As far as global warming is the motivation for that, the impact would be limited compared to banning gasoline cars.
That is because much more people use cars than use Bitcoin. And because gasoline cars use 100 percent fossil fuel, while the majority of Bitcoin mining is from renewable energy, giving a boost to renewable energy projects in the process.
Any emissions in connection with Bitcoin mining are not caused by the ASIC machines doing the mining. They are caused by the fossil fuel power plants producing the electricity. It is a good idea to phase out fossil fuel power generation. That is the cause of CO2 emissions, not whatever use is made of the electricity.