What's the tremendous externality of gas generators? People heat their own homes with natural gas and it's no big deal. How can a datacenter that is miles away be worse than that?
How can something that is a million times bigger than your home be any different, right?
The gas furnace in my basement don't have a massive jet turbine emiting high frequency noise
Its totally inefficient - burning the same gas in a co-generation plant, ideally combined with district heating, would produce the same amount of pollution and basically make use of all the energy.