An example that sort of fits this (pardon that I don't know the name off the top of my head): - One recent artist gained fame as a sculptor in the modernist tradition, using found materials, junk, etc. His art started to garner a lot of money. So, he began to go into abandoned buildings in poor neighborhoods, cut out part of the wall or the floor, sell it as his artwork -- for hundreds of thousands of dollars at the Venice Biennale & such -- and then use that money to restore and revitalize the original abandoned building that he took the material from. He turns these buildings into community centers for the neighborhood. It's quite amazing. So really the ultimate artwork is the community center that is created and the benefit to the community that it creates, the human relationships it fosters, etc.
In other examples, artists simply create events through which people can engage with each other in some structured way. Famously, Rirkrit Tiravanija served a meal in an art gallery -- it was simply a public space to interact and be human. (There are other ways to read this artwork too... it is also a very real exhibition of culture... sort of like showing a found object but the found object is a dinner party).
There is a wide array of practices here...
But there are a few clear trends. In these new works, there is often no commodity to be bought and sold. Art rests not in images or sounds (post-internet, images and sound recordings are no longer rare), but instead the artists try to address real needs of people and communities. So, whereas the author of this essay describes modern art as purely abstract, subjective, meaningless, and designed purely for the ego of the artist, these new works are selfless, generous, and designed to have a direct impact on the world. In that sense, this movement draws from histories outside of art, such as civil rights, non-profits, grass-roots activism, etc.
Hope that is a good enough primer! In my opinion this shift (from tangible art to relational art) is as significant as the early 20th century shift from representational art to abstract art. It is a sea change, and we're right in the middle of it.