The poster was shared on Facebook on the IBM System z Mainframe page. It seems to be originally put up on the Millennial Mainframer page with the following comment : "Proud to be part of z.Together we stand for generation z - customers, business partners and IBMers from around the world. 156 z enthusiasts from 100 companies in 28 countries share their passion for IBM zEnterprise".
In case you haven't come across Millennial Mainframer I'm sure you will soon. They want to offer "a fresh look at mainframes and associated Information Technology topics". They also have a site/blog which you can find over here. It's actually a group of young people or at least people at the beginning of their mainframe career who offer us a fresh look at our System z world. Do have a look at their site. It's surely worth it. And you can even join the experience or as the say it themselves :
Millennial Mainframer is always looking for permanent or guest contributors interested in publishing articles on our blog community. While we welcome contributions from mainframers of all ages, we are particularly interested in hearing from students and mainframe professionals in the first ten years of their career. To get in touch with us please email us at firstname.lastname@example.org"