'Tag soup' might not be perfect, but then neither are widely-used languages that - if they spot a single misplaced period or missing comma or a couple of extra

'Tag soup' might not be perfect, but then neither are widely-used languages that - if they spot a single misplaced period or missing comma or a couple of extra characters after a right-curly-bracket - just QUIT. Why that sort of fragility is tolerated, even lauded is beyond me. That HTML just ignores any tag it can't recognize, without stomping a foot, means all the others are available for other uses. Great!