It’s not a hard requirement per se, but rather a… sort of firm and getting firmer requirement. (The more I wrestle with reverse engineering stories, the firmer this requirement seems to get).
It’s very likely that we’ll deprecate some of the existing exercises later, if we can’t get a decent story for them.
My sense is that if we can find a down to earth (-ish) story here, then we can consider it, but without it I would prefer not to.