The section about buying new phones and the section about company investment appear to have nothing to do with one another.

The report by the Fed they cite is concerned with estimating the effect of capital reinvestment productivity gains by the firm.

Just breezing through the report it looks like the Fed is trying to explain differences in GDP between economies as a consequence of capital reinvestment. When firms buy new equipment, which could include IT equipment but also could include things like robots, backhoes, new looms, or any other piece of equipment a firm uses to produce goods or services, they should be more productive because their equipment has newer technology in it. The Fed reasons that if two major economies differ in GDP growth one of the potential explanations might be the rate of capital reinvestment firms in those economies engage in because newer equipment usually increases productivity. So more frequent investments in capital should yield faster growth in GDP. They present evidence in favor of that argument.

I don’t know how reasonable their conclusion is because I am not too familiar with their measurements which are not direct measures of capital investment and don’t really know enough about how GDP changes over time to know if this is a good explanation. It is clear, however, that the Fed is not arguing that consumers need to keep buying new phones every year or the economy will collapse or even be harmed. That is not even remotely what the report is about.