Surely there is in argument to be made that applications targeting a non-native but cross-platform runtime, like webapps, save more power than the devices running them waste. Cross-platform applications mean broader compatibility, so maybe less e-waste? Or perhaps a knock-on effect, like web apps running in browsers are trivially modifyable by extentions like uBO, which skip executing expensive tracking and advertising code that would be very difficult to stip out of a native binary. As a further knock-on, blocking those ads will make the user less likely to buy and have shipped random garbage, which reduces pollution!