At the moment, this appears to be the only (standard) way to do it, to have each related bit be its own tiddler. From a data point of view this also quite makes sense but requires a lot more (willingness and abilities for) design and setup.
With TiddlyWiki5 we have not yet been willing or able to parse (hidden) "sections" out of tiddlers, something that was a quite basic, powerful and hence an often used technique in classic TiddlyWiki.