I see where you are coming from especially as the maths operators come online, however I think that perhaps the emphasis on operator or filter may vary with the application tiddlywiki is used for. My key wiki to manage tasks projects knowledge and documentation is about lists sublists and related tiddlers so most depend on the filtering side.
I suppose it is the versatility of tiddlywiki that means it is hard to make value judgements or comparisons on how it is used without undertaking a survey.
But it is great to hear others perspective.
Tony