New phones' impact on the world is substantially more than the percentage of landfill it makes up. For example, look at it from a financial perspective. Suppose you spend 1/6 of a premium smartphone's price per month on food. You buy a new smarthphone every 2 years. So for every dollar you spend on food, you throw 25 cents at a smartphone company. Considering the regularity with which we have been doing that, how can that not have a significant impact on society?

Then again, one of the pillars of the consumerist dogma is that you can change yourself and the world by changing how you consume, which, in my opinion, is false, at least in our current socioeconomic reality. So while I think it definitely matters where you put those 25 cents, consumerism as a whole is as much a distraction as a problem.