Raw HTML permission
In my opinion, such resources should still be translatable here, and it's up to the VisualEditor team to import them and scan their safety, before putting them in their source repository and deploying them with Mediawiki updates. on all other wikis.
Or they could have made these translations behave like MediaWiki content (i.e. just restricting unsafe HTML elements (like script, embed, object, iframe, style, meta, a, or other multimedia elements...) and attributes (like on*="..." eventhandlers), or unsupported HTML elements (even if they are safe like thead, tbody, tfoot), but not portable across all target HTML versions (and other rendering engines like PDF), and all browsers (including mobile, or limited smartTV browsers that are not necessarily using HTML5 or that require some browser specific-tricks), all these being possible targets that Mediawiki supports with its parser.