It’s basically wondering why your sales aren’t going up when there are still customers to be found. Even if you saturate a market, new people are born every day, at a greater rate than they die, so one would assume you grow or fade, unless customers just like… stop buying things in a category for some reason (maybe a superior category was invented?)
The problem isn’t infinite growth in a still-growing world, it’s exactly what you posted here: Growth at all costs. The pendulum has swung too hard in favor of growth over stability. This is great for shareholders (read:everyone in America who wants to realistically retire one day) but bad for workers (read: everyone in America, regardless of whether or not they want to retire one day).
Growth will stop when nobody can buy.