Material Design isn't some immutable standard. It's a flowing, breathing, evolving design. As our own former editor Liam (now a Googler) pointed out today, the current expressions we've seen of Google Material are just one potential way to implement the changing design philosophy. So if you're eager to check the possible futures for Google's Material designs, you should probably watch this video.
It's short, but it's pretty slick, reminding us of the original video announcement which accompanied the I/O 2014 reveal for Material Design. Of course, Material has evolved quite a lot since then, changing from the perhaps overly-simplified bright and colorful boldness of the original to the more monochromatic and center button-aligned look Google seems to prefer in 2018.
Keep in mind, this isn't an official video by Google. Although the creators worked together with the Google Material Design team to create it, and although many Googlers are sharing it on social media themselves, it isn't meant to be indicative of any official stance or coming products, and it isn't endorsed by Google. Again, as noted by Liam, the interfaces shown off shouldn't be considered final designs. Seen through the lens of other various Material Design stuff shown off this year, like the Material Gallery Tool, Material Theme Editor, and the prototype app designs shown off at I/O, as well as the recent Hangouts Chat and Gmail redesign, it all looks pretty plausible overall, even if specific details may be wrong.
The video was taken down from Vimeo (curious), but the internet never forgets.