Todo lists, schedules, phone databases... everything we use databases for is really just a way to extend the power of our memory, to be able to remember what our conscious mind may not currently have access to.
There are many different databases out there—and good ones—which this mode is not trying to replace. Rather, it's how that data gets there that's the question. Most of the time, we just want to say “Remember so-and-so's phone number, or that I have to buy dinner for the cats tonight.” That's the FACT. How it's stored is really the computer's problem. But at this point in time, it's most definitely also the user's problem, and sometimes so laboriously so that people just let data slip, rather than expend the effort to record it.
“Remember” is a mode for remembering data. It uses whatever back-end is appropriate to record and correlate the data, but its main intention is to allow you to express as little structure as possible up front. If you later want to express more powerful relationships between your data, or state assumptions that were at first too implicit to be recognized, you can “study” the data later and rearrange it. But the initial “just remember this” impulse should be as close to simply throwing the data at Emacs as possible.
Have you ever noticed that having a laptop to write on doesn't actually increase the amount of quality material that you turn out, in the long run? Perhaps it's because the time we save electronically in one way, we're losing electronically in another; the tool should never dominate one's focus. As the mystic Farīd ud-Dīn ʿAṭṭār wrote: “Be occupied as little as possible with things of the outer world but much with things of the inner world; then right action will overcome inaction.”
If Emacs could become a more intelligent data store, where brainstorming would focus on the ideas involved—rather than the structuring and format of those ideas, or having to stop your current flow of work in order to record them—it would map much more closely to how the mind (well, at least mine) works, and hence would eliminate that very manual-ness which computers from the very beginning have been championed as being able to reduce.