For a specific example of real problems caused by killing Google News Archive search, it affected the work of Wikipedia editors. I and a lot of other editors had found it very useful as a high-quality and fast way to find good sources for articles we were working on (https://en.wikipedia.org/wiki/Wikipedia:Free_English_newspap...). There's not really anything else like it, so you end up combing through tons of general Google results that don't qualify as reliable sources in order to find a few newspaper articles.