He may have worked on one in 2014, but he clearly stopped working on it. Being volunteers, people work according to their available time and interests.

There was a bounty funded by a number of us in 2014 which successfully produced four GUIs in early-mid 2014 which were available and for a time listed on the web site "choose-a-wallet" page. Those weren't maintained so most were eventually removed from the page, but the lightWallet GUI wallet (still maintained, now on version 2) is still there.

That is how decentralized open source projects work. If you want to contribute and have relevant skills, you are welcome too.

Reference: https://getmonero.org/getting-started/choose