The article is bad and the author should feel bad. (Zoidberg noises)

Replacing parts of concrete by e.g. carbon is nothing new. Using graphite as a cheap graphene proxy is cheap and effective. (Graphite is basically graphene and extra bits and pieces)

Posing this as a way to get Coffee grounds out of landfills is misleading as there is no reason to send them there to begin with.

They don't highlight why coffee grounds may be better suited than other organic waste.

You can use manufactured sand in concrete to get a very similar end product. Changing processes is work and hence avoided. But it is perfectly possible.