IMO it's not. First of all, I doubt many of the engineers here are actively selling the technology to the oil and gas companies directly, or even working on features that are especially designed for oil and gas companies - if they are, I think they have a little more of a case.
Second of all, the relevant point here is that cloud computing capabilities are by default available to any purchaser, just as encryption is available to any user of products that contain it. From a utilitarian standpoint, I think most would agree that encryption and cloud computing are of overall benefit to the world. One might believe that, from a utilitarian standpoint, it would be better to not provide material assistance to oil and gas companies, since they do result in a lot of damage to the planet (although I personally believe the more effective route is to instead actively favor the development and deployment of renewable energy). But that argument is the same in principle as one favoring restrictions on the use of encryption by child pornographers for utilitarian purposes, to say nothing about restrictions on the use of encryption by enemies of your nation (which was the basic argument by the US government in the 1990s about restricting the use of encryption by non-Americans).
Google had a "VP of Oil, Gas, and Energy" so it's not like they are building off-the-shelf software that oil and gas companies happen to purchase. Google is making a concerted effort to accommodate those companies specifically.
I suspect the main function of that VP is sales and marketing, not inventing different technology. The technology remains essentially usable by everyone.
Second of all, the relevant point here is that cloud computing capabilities are by default available to any purchaser, just as encryption is available to any user of products that contain it. From a utilitarian standpoint, I think most would agree that encryption and cloud computing are of overall benefit to the world. One might believe that, from a utilitarian standpoint, it would be better to not provide material assistance to oil and gas companies, since they do result in a lot of damage to the planet (although I personally believe the more effective route is to instead actively favor the development and deployment of renewable energy). But that argument is the same in principle as one favoring restrictions on the use of encryption by child pornographers for utilitarian purposes, to say nothing about restrictions on the use of encryption by enemies of your nation (which was the basic argument by the US government in the 1990s about restricting the use of encryption by non-Americans).