Design languages like Windows Modern (or whatever the design language that used to be called "Metro" is called now) and Material Design are more clear and specific things than "flat" or "skeumorphic" design, which are just descriptors of one aspect of the design approach
And, sure, most of them are evolutions of things that have gone previously and combine pre-existing elements without being revolutionary departures. But that doesn't make them not clear and specific things.
You're taking "isn't a thing" too literally. Yes, design languages are things. But material design is not a complete school of thought. It's one company's design language. Other companies are going to want their own design language, to distinguish themselves from their competitors. They can take inspiration from material design, but whatever you make can't be called material design. Google defines what material design is, and only they can put the material design stamp on something.
And even though material design adds some depth, it's still pretty flat. Sure, cards and panels have a slight drop shadow behind them, but buttons still lack any bevel or border. This isn't much different from current flat designs. Many of them include depth in select places.
> But material design is not a complete school of thought.
Yes, it is. Its actually more of a "complete school of thought" than, e.g., "flat design", which is a vague, ill-defined, poorly-bounded element of an approach to visual design, not a complete school of thought on UI design.
> Other companies are going to want their own design language, to distinguish themselves from their competitors.
Some may, some may not. Design language is hardly the only potential axis of product or company differentiation. Furthermore, you can differentiate on design within the parameters of a design language like Material Design, because -- while fairly comprehensive -- it doesn't dictate all aspects of design. Defining consistency in the areas Material Design leaves open produces a distinct design that is still completely within the bounds of the Material Design.
You're confusing complete with specific. The material design language offers specific solutions to specific cases. But what designers need more is a general theory they can apply to any situation. And the theory behind material design doesn't fundamentally differ from flat design, other than it's focus on animations. It still shares the principles espoused by flat design people (authentically digital interfaces, minimalism).
No, I'm not, I'm saying design languages with well-defined motivating principles like Material Design and Microsoft's ex-Metro language are both more complete schools of thought on design (starting with identified principles that cover broader scope of design problems) and more specific, well-defined approaches to design/interaction (clearly defining both foundational principles and the applications of those to specific areas of design) than things like "flat" design.
Yes, it is.
> It's Google's name for their design language
Which is a thing.
> which is just flat design with more animations.
And depth, so not flat.
Design languages like Windows Modern (or whatever the design language that used to be called "Metro" is called now) and Material Design are more clear and specific things than "flat" or "skeumorphic" design, which are just descriptors of one aspect of the design approach
And, sure, most of them are evolutions of things that have gone previously and combine pre-existing elements without being revolutionary departures. But that doesn't make them not clear and specific things.