Comment by MostlyStable

That's what we are usually taught, but it doesn't actually seem to be the case. In the smartphone market in particular, as the market itself has grown, the offerings have all seemed to converge on a relatively uniform feature set. Niche phones for niche markets have slowly been weeded out. I don't understand why this is the case, but empirically it seems to be so. That's not to say that there are no weird, niche phones anymore, but it does seem to be the case that there are fewer of them than in the past, when it seems to me that we should expect the opposite: as the market grows, the absolute size of proportionally tiny "niche" markets should also grow, which seems like it should support a greater diversity of weird phones.