I think it strongly evokes a line on a paper form, which indicates a place where the user must fill out a field (and fits with the recurring paper metaphor). If I'd never used a computer before, I think I would figure this out based on the context clues.

So while it may not fit current UI paradigms, it might be better? I applaud Material Design for attempting to move things forward in this way.

The issue is that the computer screen is not a paper form. You can't just fill out forms wherever you see dotted lines/horizontal rules(hr tags). Unlike paper pages, most of the HTML pages are read only / not content editable.

Yeah, my brief exploration with user feedback in a material style form of that sort returned of a lot expectations especially on HTML pages that the underlined things were "weird links" not editable form fields and they didn't know how to edit the content. Some of those were even Android users presumably seeing the same style of fields in their day-to-day apps. One said they hated it in Android apps too but had no way to control it.

Fair point, I'll that that into account and see what I can do. Thanks for your feedback