I think there was some discussion a while ago, that the "Simple" modules are sometimes "too simple" and inflexible if/when circumstances change. More or less, the "Simple" modules usually make "their" thing simple to use, by including boilerplate/wrapping default behaviour around a complex thing (which makes it more difficult to deviate later, when it may be necessary).

The "Tiny" modules more or less give you only the bare necessities to build upon, which enables you to start simple and later make it just as complex as needed.