Colleagues, are there plans to combine the .glyphs sources for Noto Serif & Noto Serif Display into one source? And the same for Noto Sans and Noto Sans Display?

simoncozens commented yesterday
We decided to do away with the "Display" versions, as they were ill-defined. (Not really opsz, not really contrast, and not consistent between Sans/Serif.) Maybe we'll bring them back one day! (Probably not.)

https://github.com/notofonts/latin-greek-cyrillic/issues/436#issuecomment-1577379159
The "display" version was not exactly optical size and not exactly contrast, and was a different implementation between serif and sans. It didn't really fit into any of the models of font variation that we support elsewhere. So they need re-thinking, harmonising, and re-drawing.