People don’t have brand new laptops all the time. Often, they have crappy 10 year old laptops because they can’t afford anything better, especially in poorer parts of the world.
In MicroSD cards flash is cheap. But unfortunately, most phones don’t come with MicroSD slots anymore, and instead they come with huge storage markups. According to Apple, which controls a big section of the market, a Big Mac gets you a whopping 5GB of storage, that’s if you buy today. But with a 5 year old phone, a Big Mac back then would get you 1GB of storage that you use today. And in many countries, most people make less than a Big Mac per day.